Merge pull request 'Keep disabled controls in the accessibility tree so their reason is announced' (#49 ) from fix/disabled-control-accessibility into main

Reviewed-on: #49
Give the terminal and Add Project buttons a reason a screen reader can hear
2026-09-02 18:53:20 +00:00 · 2026-09-02 09:08:57 -07:00 · 2026-09-02 09:08:50 -07:00 · 2026-08-28 20:21:01 +00:00 · 2026-08-28 20:20:54 +00:00 · 2026-08-28 13:11:26 -07:00
42 changed files with 3389 additions and 486 deletions
@@ -1,274 +0,0 @@
-name: Publish AUR Package
-
-# Builds and pushes the `triple-c-bin` AUR package (packaging/arch/PKGBUILD)
-# for a given release, or the latest one if none is given. Manual dispatch
-# only — deliberately not triggered by `release` or `push`, for the same
-# reason sync-release.yml (removed in triple-c#32) never worked safely as an
-# automatic trigger: this repo's releases are assembled by build-app.yml
-# across three separate platform jobs, and there is no single automatic event
-# that fires only once everything (including the Linux .deb this workflow
-# needs) is actually uploaded. A human deciding "this release is ready, go
-# package it" is the correct trigger, the same reasoning
-# backfill-releases.yml already uses for its own manual-only GitHub sync.
-#
-# ## What this does and does not do
-#
-# It renders `packaging/arch/PKGBUILD` for one specific version (real
-# download URL, real sha256sums — never guessed; see the resolve-asset step)
-# and pushes the rendered PKGBUILD plus a regenerated `.SRCINFO` to AUR. It
-# does NOT commit anything back to this repo — `packaging/arch/PKGBUILD` stays
-# a hand-maintained template with a placeholder version, and every real,
-# published version lives only in AUR's own git history, which is where a
-# PKGBUILD's revision history is expected to live. A corollary worth knowing:
-# a hand-edit made directly in the AUR repo (outside this workflow) is
-# silently overwritten the next time this runs, since every run renders fresh
-# from this repo's template rather than starting from AUR's current state.
-#
-# ## Required secret
-#
-# `AUR_SSH_PRIVATE_KEY` — an SSH private key registered against an AUR
-# account that has already created (or been given co-maintainer access to)
-# the `triple-c-bin` package. This workflow cannot create that AUR account or
-# register the key for you — both are manual, one-time steps on
-# https://aur.archlinux.org. Until this secret exists, every run fails at the
-# "Push to AUR" step with a clear error rather than silently doing nothing.
-on:
-  workflow_dispatch:
-    inputs:
-      version:
-        description: >-
-          Release version to package, without a leading "v" (e.g. "0.4.14").
-          Leave empty to use the latest published GitHub release.
-        required: false
-
-env:
-  GITHUB_REPO: shadowdao/triple-c
-  AUR_REPO: ssh://aur@aur.archlinux.org/triple-c-bin.git
-
-jobs:
-  publish:
-    runs-on: ubuntu-latest
-    steps:
-      - name: Checkout
-        uses: actions/checkout@v4
-
-      - name: Resolve version and find the Linux asset
-        id: resolve
-        env:
-          VERSION_INPUT: ${{ inputs.version }}
-          GH_PAT: ${{ secrets.GH_PAT }}
-        run: |
-          set -euo pipefail
-
-          # Authenticated when the secret is available (it is, everywhere
-          # else in this repo's workflows) to avoid the unauthenticated
-          # 60-requests/hour-per-IP cap; still works without it, just at that
-          # lower limit, since this hits nothing but a public repo's public
-          # releases.
-          AUTH=()
-          [ -n "${GH_PAT}" ] && AUTH=(-H "Authorization: Bearer ${GH_PAT}")
-
-          if [ -z "${VERSION_INPUT}" ]; then
-            echo "No version given — resolving the latest GitHub release"
-            RELEASE_JSON=$(curl -fsS "${AUTH[@]}" "https://api.github.com/repos/${GITHUB_REPO}/releases/latest")
-          else
-            echo "Using requested version ${VERSION_INPUT}"
-            RELEASE_JSON=$(curl -fsS "${AUTH[@]}" "https://api.github.com/repos/${GITHUB_REPO}/releases/tags/v${VERSION_INPUT}")
-          fi
-
-          TAG=$(echo "$RELEASE_JSON" | jq -r '.tag_name')
-          VERSION="${TAG#v}"
-          echo "Resolved to ${TAG}"
-
-          # Discovered from the real release, not assumed: Tauri names the
-          # asset after `productName` verbatim ("Triple-C"), not the
-          # lowercase Cargo binary name, and asset naming is exactly the kind
-          # of thing that silently drifts if a future Tauri upgrade changes
-          # bundler defaults — a hardcoded pattern here would then 404
-          # forever until someone noticed. `head -1` guards against a release
-          # somehow carrying more than one matching asset, which would
-          # otherwise pass the emptiness check below and then break the
-          # download step with two URLs on one line.
-          DEB_URL=$(echo "$RELEASE_JSON" | jq -r '.assets[] | select(.name | endswith("_amd64.deb")) | .browser_download_url' | head -1)
-          DEB_NAME=$(echo "$RELEASE_JSON" | jq -r '.assets[] | select(.name | endswith("_amd64.deb")) | .name' | head -1)
-          if [ -z "$DEB_URL" ] || [ "$DEB_URL" = "null" ]; then
-            echo "No *_amd64.deb asset found on release ${TAG}" >&2
-            exit 1
-          fi
-          echo "Found asset: ${DEB_NAME}"
-
-          echo "version=${VERSION}" >> "$GITHUB_OUTPUT"
-          echo "tag=${TAG}" >> "$GITHUB_OUTPUT"
-          echo "deb_url=${DEB_URL}" >> "$GITHUB_OUTPUT"
-          echo "deb_name=${DEB_NAME}" >> "$GITHUB_OUTPUT"
-
-      - name: Download the release asset and compute real checksums
-        id: checksums
-        env:
-          DEB_URL: ${{ steps.resolve.outputs.deb_url }}
-          DEB_NAME: ${{ steps.resolve.outputs.deb_name }}
-          TAG: ${{ steps.resolve.outputs.tag }}
-        run: |
-          set -euo pipefail
-          curl -fsSL -o "${DEB_NAME}" "${DEB_URL}"
-          curl -fsSL -o LICENSE "https://raw.githubusercontent.com/${GITHUB_REPO}/${TAG}/LICENSE"
-
-          echo "deb_sha256=$(sha256sum "${DEB_NAME}" | cut -d' ' -f1)" >> "$GITHUB_OUTPUT"
-          echo "license_sha256=$(sha256sum LICENSE | cut -d' ' -f1)" >> "$GITHUB_OUTPUT"
-
-      - name: Render PKGBUILD
-        id: render
-        env:
-          VERSION: ${{ steps.resolve.outputs.version }}
-          DEB_NAME: ${{ steps.resolve.outputs.deb_name }}
-          DEB_SHA256: ${{ steps.checksums.outputs.deb_sha256 }}
-          LICENSE_SHA256: ${{ steps.checksums.outputs.license_sha256 }}
-        run: |
-          set -euo pipefail
-          mkdir -p rendered
-          cp packaging/arch/PKGBUILD rendered/PKGBUILD
-          cd rendered
-
-          # Plain string replacement throughout, not sed — the source URL
-          # contains slashes and the repo name does too, and getting a sed
-          # delimiter choice AND its escaping right for that is exactly the
-          # kind of thing that looks correct, passes review, and breaks the
-          # next time someone touches it. `re.sub` with `count=1` and an
-          # exact `.format`-free literal match is boring and that's the
-          # point: every substitution below fails loudly (an assertion /
-          # the checks after) rather than silently no-op'ing if the
-          # template's shape ever drifts from what this expects.
-          #
-          # pkgrel resets to 1 for a new pkgver — a packaging-only fix to the
-          # same upstream version (a dependency bump, say) is what pkgrel is
-          # for, and this workflow always republishes the current PKGBUILD
-          # verbatim rather than incrementing anything, so 1 is always
-          # correct for what this workflow does. It is NOT correct for a
-          # dependency-only fix republished at the *same* pkgver: pkgrel
-          # would be forced back to 1, and no existing installation sees an
-          # upgrade. That case needs a manual pkgrel bump in the template
-          # before dispatching, which this workflow has no input for.
-          python3 - "$VERSION" "$DEB_NAME" "$DEB_SHA256" "$LICENSE_SHA256" "$GITHUB_REPO" <<'PY'
-          import re, sys
-          version, deb_name, deb_sha, license_sha, github_repo = sys.argv[1:6]
-
-          with open("PKGBUILD") as f:
-              text = f.read()
-
-          text, n = re.subn(r"(?m)^pkgver=.*$", f"pkgver={version}", text, count=1)
-          assert n == 1, "pkgver=... line not found"
-          text, n = re.subn(r"(?m)^pkgrel=.*$", "pkgrel=1", text, count=1)
-          assert n == 1, "pkgrel=... line not found"
-
-          old_source = (
-              f'source=("Triple-C_${{pkgver}}_amd64.deb::'
-              f'https://github.com/{github_repo}/releases/download/v${{pkgver}}/'
-              f'Triple-C_${{pkgver}}_amd64.deb"'
-          )
-          new_source = (
-              f'source=("{deb_name}::'
-              f'https://github.com/{github_repo}/releases/download/v{version}/{deb_name}"'
-          )
-          assert old_source in text, "source=() line does not match the expected template shape"
-          text = text.replace(old_source, new_source, 1)
-
-          old_sums = "sha256sums=('SKIP'\n            'SKIP')"
-          assert old_sums in text, "sha256sums=() placeholders not found"
-          text = text.replace(old_sums, f"sha256sums=('{deb_sha}'\n            '{license_sha}')", 1)
-
-          with open("PKGBUILD", "w") as f:
-              f.write(text)
-          PY
-
-          grep -q "pkgver=${VERSION}$" PKGBUILD
-          ! grep -q "SKIP" PKGBUILD
-
-      - name: Validate with makepkg and namcap
-        run: |
-          set -euo pipefail
-
-          # A bind mount (`docker run -v "$PWD/...":/work`) is the more
-          # obvious way to write this, and was the first draft — but on a
-          # containerized Gitea act_runner job, `$PWD` is a path inside this
-          # job's own container, which the daemon's host cannot resolve; the
-          # mount would silently attach an empty directory instead of failing
-          # loudly. `docker cp` moves real bytes across that boundary
-          # regardless of where the daemon actually lives, which is what
-          # makes this work under both a bind-mount-capable runner and a
-          # containerized one.
-          docker pull archlinux:latest
-          CID=$(docker create -w /work archlinux:latest bash -c '
-            set -euo pipefail
-            pacman -Syu --noconfirm --needed base-devel namcap sudo git openssh >/dev/null
-            useradd -m builder
-            chown -R builder:builder /work
-            echo "builder ALL=(ALL) NOPASSWD: ALL" > /etc/sudoers.d/builder
-            sudo -u builder bash -c "cd /work && makepkg --printsrcinfo > .SRCINFO"
-            sudo -u builder bash -c "cd /work && makepkg -s --noconfirm"
-            echo "--- namcap ---"
-            NAMCAP_OUT=$(sudo -u builder bash -c "cd /work && namcap PKGBUILD *.pkg.tar.*" || true)
-            echo "$NAMCAP_OUT"
-            # Matches "triple-c-bin E:", "PKGBUILD (triple-c-bin) E:" and any
-            # split-package variant ("triple-c-bin-debug E:") alike — namcap
-            # uses more than one line shape for its two rule families, and
-            # namcap itself exits 0 regardless of what it reports, so this
-            # grep is the only thing standing between an E: and a green job.
-            if echo "$NAMCAP_OUT" | grep -q " E: "; then
-              echo "namcap reported an error — see above" >&2
-              exit 1
-            fi
-          ')
-          mkdir -p rendered
-          docker cp rendered/. "${CID}:/work"
-          # `docker start -a` streams output and its exit code is the
-          # container's own — the same failure this would have hit with a
-          # bind mount still fails the job the same way.
-          docker start -a "${CID}"
-          docker cp "${CID}:/work/.SRCINFO" rendered/.SRCINFO
-          docker rm -f "${CID}" >/dev/null
-
-      - name: Push to AUR
-        env:
-          AUR_SSH_PRIVATE_KEY: ${{ secrets.AUR_SSH_PRIVATE_KEY }}
-          VERSION: ${{ steps.resolve.outputs.version }}
-        run: |
-          set -euo pipefail
-          if [ -z "${AUR_SSH_PRIVATE_KEY}" ]; then
-            echo "AUR_SSH_PRIVATE_KEY is not set — see this workflow file's header comment for" >&2
-            echo "the one-time AUR account setup this needs before it can publish anything." >&2
-            exit 1
-          fi
-
-          mkdir -p ~/.ssh
-          # Created with the final mode before any bytes land in it, rather
-          # than a plain redirect followed by chmod, which leaves the key
-          # world-readable for whatever window falls between the two calls.
-          install -m 600 /dev/null ~/.ssh/aur
-          echo "${AUR_SSH_PRIVATE_KEY}" > ~/.ssh/aur
-          # TOFU, not verification — accepted here because pinning AUR's
-          # actual host key needs a value fetched from somewhere trusted
-          # ahead of time, which this workflow doesn't have, and getting a
-          # pinned value wrong fails every future run rather than just this
-          # one. A keyscan failure below surfaces later as an opaque
-          # "Host key verification failed" rather than a clear one here.
-          ssh-keyscan -H aur.archlinux.org >> ~/.ssh/known_hosts 2>/dev/null
-          export GIT_SSH_COMMAND="ssh -i ~/.ssh/aur -o IdentitiesOnly=yes -o UserKnownHostsFile=~/.ssh/known_hosts"
-
-          git clone "${AUR_REPO}" aur-repo
-          cp rendered/PKGBUILD rendered/.SRCINFO aur-repo/
-          cd aur-repo
-          git config user.name "Triple-C CI"
-          git config user.email "noreply@triple-c.invalid"
-          git add PKGBUILD .SRCINFO
-          if git diff --cached --quiet; then
-            echo "No change from what's already published on AUR for ${VERSION}"
-            exit 0
-          fi
-          git commit -m "triple-c-bin: update to ${VERSION}"
-          # AUR itself uses `master`, which is what a fresh, not-yet-created
-          # AUR package's empty repo advertises on clone — but the *local*
-          # branch name after cloning an empty repo falls back to whatever
-          # this runner's `init.defaultBranch` is if the server sends no
-          # symref, so naming the destination explicitly is what keeps this
-          # working if that default is ever `main` instead of `master`.
-          git push origin HEAD:master
@@ -552,6 +552,151 @@ survived 92 commits and fourteen days in the public GitHub mirror, past five aud
 independent reviews, because every one of them read the code under change and this sat in a test
 nobody had reason to open. Fixtures are never live values; there is no case where they need to be.

+## Settings export/import
+
+`commands::settings_export_commands`, `storage::settings_crypto`, `models::settings_export`
+(triple-c#35). Exports the *host* environment — global `AppSettings` plus the global secrets that
+live in the OS keychain instead: the shared Claude Code OAuth login and the model gateway's two
+keys. Per-project settings, per-project secrets, and anything in a project's Docker volumes are
+deliberately out of scope — this is not a project backup.
+
+- **`AppSettings` is not entirely the non-secret shape it looks like, and a review of this feature
+  caught the one place that isn't.** `WebTerminalSettings::access_token` is a live bearer
+  credential for a server that binds every interface — exporting `AppSettings` wholesale would
+  have carried it along as if it were as inert as a port number, and importing it would have
+  applied `web_terminal.enabled` and the token together with no more warning than any other
+  setting, letting a crafted export silently stand up a LAN-listening terminal on the next launch.
+  `export_settings`/`apply_settings_import` carve this one field out into `ExportedSecrets`
+  instead, with the same "only overwrite what the import actually has" treatment as the other
+  three secrets — except "leave it alone" has to be done by hand in `apply_settings_import`, since
+  unlike the keychain secrets this one lives inside the `AppSettings` blob that gets replaced
+  wholesale. `SettingsImportPreview::enables_web_terminal` also exists because of this: `enabled`
+  and the token are independent fields, and "this turns on a listening service" must not hide
+  inside a generic "settings replaced" summary. Read this as the standing example of the class of
+  thing to keep checking for in this feature, not a one-off fixed bug — any other field that looks
+  like config but is actually a live credential would have the same problem.
+- **Encrypted because it can carry live credentials, not for appearance's sake.** Argon2id derives
+  a 256-bit key from the user's password (memory-hard — meaningfully resistant to GPU/ASIC
+  brute-forcing, unlike PBKDF2 at any reasonable iteration count), AES-256-GCM does the actual
+  encryption. A wrong password fails GCM's authentication tag rather than producing silent
+  garbage. The salt and nonce are not secret and are written in the clear in the file's own
+  header — the salt's job is only to make two exports of the same password derive different keys,
+  and the nonce's only requirement is per-encryption uniqueness, which a fresh random draw on
+  every export already gives it.
+- **The save/open dialogs are opened from Rust**, the same boundary `file_commands.rs`'s
+  `pick_save_path`/`pick_files_to_upload` draw and document at length: a frontend-driven dialog
+  handing Rust a host path string is the exact shape of bug that produced this app's past
+  criticals. `preview_settings_import` resolves the chosen path itself and remembers it
+  (`AppState::pending_settings_import`) so `apply_settings_import` re-reads the same file without
+  a path ever crossing back over IPC. It also pins a hash of the file's ciphertext next to that
+  path, and `apply_settings_import` refuses to proceed if the file on disk no longer matches it —
+  otherwise confirming a preview would not actually be binding on what gets applied, which matters
+  given this feature's own threat model: a file shared between people may sit in a synced or
+  otherwise shared directory that changes between the two calls.
+- **The decrypted payload is not cached between preview and apply — only the password is reused.**
+  The frontend holds the password in React state and passes it to both calls; nothing in Rust
+  holds decrypted plaintext — secrets included — in memory for longer than one command's
+  execution, so `apply_settings_import` always re-decrypts rather than reusing anything
+  `preview_settings_import` computed. `preview_settings_import` returns counts and presence flags
+  only (`SettingsImportPreview`), never a secret value, so it's safe to hand to the frontend and
+  render directly.
+- **Import replaces settings wholesale, but only writes secrets actually present in the file.**
+  An import is "restore this environment," so the settings half is a full replace, not a
+  field-by-field merge. Secrets are different on purpose: an absent secret in the export means
+  "the source machine never had this configured," not "delete this on import" — a user who wants
+  to clear a secret already has dedicated UI for that (signing out of shared auth, clearing the
+  gateway key). Secrets are restored *before* the settings replace runs, not after — replacing
+  settings is what triggers `reconcile_gateway`, and restoring the other way round leaves a real
+  window where a gateway recreation happens against the destination's old keys.
+- **A restored gateway secret nudges a running gateway container to recreate itself, even when
+  nothing about the gateway's *shape* changed.** `reconcile_gateway`'s `gateway_shape_changed` only
+  compares port/provider/base URL/models — deliberately, since that's what's rendered into the
+  container's config — so a secret-only change (same shape, new key) is invisible to it. Left
+  alone, a running container would keep serving the old key material indefinitely after an import
+  that restored a new one. `apply_settings_import` tracks whether either gateway secret was
+  actually written and, if the gateway is enabled and its container both exists and is running,
+  calls `docker::gateway::ensure_gateway_running` directly afterward — its own fingerprint already
+  includes the secret rotation id (`storage::secure::get_gateway_secret_version`), so it recreates
+  exactly when it should and no more.
+- **A keychain write failing during import is reported back, not only logged.** Each of the three
+  `secure::store_*` calls collects its error into `SettingsImportOutcome::secret_restore_warnings`
+  in addition to logging it — an import that silently restores two of three secrets but not the
+  third must not read as unqualified success just because the settings half of the import (which
+  runs after, and is validated before any of this) went through. `apply_settings_import` returns
+  `SettingsImportOutcome { settings, secret_restore_warnings }` rather than bare `AppSettings` for
+  this reason; `ImportSettingsModal` shows any warnings alongside the "Settings imported" message.
+- **The imported settings are validated *before* any secret is written, not just before the
+  settings replace.** `apply_settings_import` calls
+  `settings_commands::validate_settings_update(&current, &settings)` — the same checks
+  `update_settings` runs internally, pulled out into its own function specifically so this caller
+  can run them first — and only proceeds to the three keychain writes if that passes. A review
+  caught the earlier ordering: writing secrets first meant a rejected import (a bad env var name, a
+  disallowed host path) still left the keychain overwritten with the file's secrets while the
+  settings themselves stayed unchanged, a silently half-applied state the error message gave no
+  hint of.
+- **`read_and_decrypt` checks `format_version` before attempting to parse the full payload, not
+  after.** A version bump that isn't deserialize-compatible is exactly the case that check exists
+  for, and parsing the full struct first would fail on the shape mismatch before the version check
+  ever ran. Neither error path interpolates what `serde_json` actually says into the message
+  shown to the user — its type-mismatch errors quote the offending value inline, and the plaintext
+  here can hold a live credential.
+- **The 8-character password minimum is enforced in `export_settings` itself, not only in the
+  export modal.** The frontend minimum is a UX nudge; the Rust command is the actual boundary a
+  weak password has to cross, and Argon2id's memory-hardness buys little against an attacker who
+  can just try a short password directly. Measured with `.chars().count()` (Unicode scalar values)
+  rather than `.len()` (bytes), to stay as close as this pair of languages allows to the frontend's
+  `.length` check (UTF-16 code units) — the two only diverge on astral-plane characters. The
+  derived key and both plaintext buffers — the payload built for export, and whatever `decrypt`
+  recovers on import — are wrapped in `zeroize::Zeroizing` for the same reason every other secret
+  in this codebase gets handled carefully — cheap insurance (`zeroize` is already pulled in
+  transitively via `aes-gcm`) for material that exists only to hold or produce live credentials.
+- **The preview also discloses non-blank custom base URLs** (`global_ollama`, `global_llamacpp`,
+  `global_openai_compatible`, `gateway.api_base`) so an import that would redirect model traffic to
+  a different server is visible in the confirmation dialog rather than discovered later — these are
+  endpoints, not secrets, so `SettingsImportPreview` carries and `describeImport` renders the actual
+  URL rather than just a presence flag. `describeImportWarnings` additionally calls out a web
+  terminal token that arrives with the terminal left *off*: `start_web_terminal` only mints a fresh
+  token when none is already set, so a planted token would otherwise activate silently the next
+  time someone turns the terminal on, with no import-time signal that it wasn't freshly generated.
+- **The preview also discloses a custom Docker image, and warns on one every time — not just on
+  change.** `custom_image_name`/`image_source` weren't in scope for the base-URL disclosure above,
+  but a review pointed out they're a sharper version of the same problem: this is the image *every*
+  project container is created from (`models::container_config::resolve_image_name`), so a crafted
+  export pointing it at an attacker-controlled image is a path to running arbitrary code with
+  whatever a project's containers are allowed to reach, not merely a redirected API endpoint.
+  `describeImportWarnings` fires on `image_source == Custom` unconditionally rather than only when
+  it differs from the destination's current value, since re-importing the same risky configuration
+  is still worth surfacing every time a user confirms an import.
+- **Every free-form string a preview surfaces is sanitized and length-capped before it's built.**
+  `SettingsImportPreview::from_payload`'s `sanitize_for_preview` strips control characters and caps
+  at 100 characters (`MAX_PREVIEW_STRING_LEN`) for every base URL and the custom image name — a
+  review noted that, unlike the count- and boolean-derived fields the preview started with, these
+  are verbatim strings from a not-yet-trusted decrypted payload rendered directly into the
+  confirmation dialog. Unbounded, a single pathological value (very long, or holding embedded
+  newlines) could push the security warnings above the scroll fold in the dialog that exists
+  specifically to make them unmissable — the frontend's `<li>`/warning boxes also get `break-all`
+  as a second layer against the same failure mode.
+
+## Packaging
+
+Linux ships as `.deb`, `.rpm` and AppImage, all three built by `build-app.yml` (releases) and
+`build-app-preview.yml` (the PR check). **There is deliberately no Arch package.** A
+`triple-c-bin` `PKGBUILD` and a `publish-arch-package.yml` existed and were removed; they live on
+`hold/arch-packaging`. Do not re-add them without the piece that was always missing: the package
+was never on the AUR, so it was a manual `pacman -U` of a downloaded file — the same gesture as
+the AppImage, for a second artifact to keep working. Being `workflow_dispatch`-only it also
+reached 1 release in 28, while `HOW-TO-USE.md` told Arch users to download it from every release.
+An AUR account and its SSH key as a repo secret are what would make it worth having; until then
+the AppImage is the Arch story.
+
+`scripts/install-appimage.sh` is the desktop-integration half, and it exists because an AppImage
+has no installer: it extracts the bundled icons into `~/.local/share/icons/hicolor` and writes a
+`.desktop` entry. It **rewrites** the `Exec` line rather than copying the bundled entry — the
+bundled one is `Exec=triple-c`, which resolves only inside the AppImage's own mount, so a
+verbatim copy yields a launcher entry that starts nothing. It keeps `StartupWMClass` exactly as
+the bundle sets it, which is what lets the shell match the window to the entry. Extraction uses
+`--appimage-extract`, which needs no FUSE, so the script works before `fuse2` is installed.
+
 ## Testing

 Frontend tests use Vitest with jsdom environment and React Testing Library. Setup file at `src/test/setup.ts`. Run a single test file:
@@ -6,6 +6,7 @@ Triple-C (Claude-Code-Container) is a desktop application that runs Claude Code

 ## Table of Contents

+- [Installation](#installation)
 - [Prerequisites](#prerequisites)
 - [First Launch](#first-launch)
 - [The Interface](#the-interface)
@@ -32,6 +33,63 @@ Triple-C (Claude-Code-Container) is a desktop application that runs Claude Code

 ---

+## Installation
+
+Download the build for your platform from [GitHub Releases](https://github.com/shadowdao/triple-c/releases/latest).
+
+| Platform | File | Install |
+|----------|------|---------|
+| **Windows** | `Triple-C_<version>_x64-setup.exe` or `.msi` | Run the installer. |
+| **macOS** | `Triple-C_<version>_universal.dmg` | Open the `.dmg` and drag Triple-C to Applications. |
+| **Debian / Ubuntu** | `Triple-C_<version>_amd64.deb` | `sudo apt install ./Triple-C_<version>_amd64.deb` |
+| **Fedora / RHEL** | `Triple-C-<version>-1.x86_64.rpm` | `sudo dnf install ./Triple-C-<version>-1.x86_64.rpm` |
+| **Arch / CachyOS / other Linux** | `Triple-C_<version>_amd64.AppImage` | `chmod +x` it, then run it directly. See the AppImage notes below. |
+
+> **macOS note:** The app is not signed or notarized. On first launch, macOS Gatekeeper may block it — right-click the app and select "Open" to bypass, or remove the quarantine attribute: `xattr -cr /Applications/Triple-C.app`.
+
+> **AppImage note:** Two things are worth knowing. Running an AppImage needs FUSE 2, which Arch and CachyOS do not install by default — `sudo pacman -S fuse2` once, or run it with `--appimage-extract-and-run` to sidestep FUSE entirely. And an AppImage is just an executable file: nothing registers it with the desktop, so it will not appear in your app launcher on its own. Run [`scripts/install-appimage.sh`](scripts/install-appimage.sh) to add a launcher entry and icons — see [Adding an AppImage to the app launcher](#adding-an-appimage-to-the-app-launcher).
+
+> **No Arch package.** There was a `triple-c-bin` `.pkg.tar.zst` attached to some releases, built by a maintainer-triggered workflow. It was never on the AUR, so installing it meant downloading a file and running `pacman -U` — no better than the AppImage — and being manual-only it reached 1 release in 28, which made the promise of it worse than not making it. The `PKGBUILD` and its workflow are preserved on the `hold/arch-packaging` branch if an AUR package is ever worth doing properly.
+
+### Adding an AppImage to the app launcher
+
+An AppImage is a single executable file and nothing else. It carries a `.desktop`
+entry and icons *inside* itself, but nothing on your system ever reads them,
+because nothing installed it — so it will not show up in your app launcher, and
+running it from a file manager gives you a generic icon in the taskbar.
+
+Put the AppImage somewhere stable first — `~/Apps` or `~/.local/bin`, not
+`~/Downloads` — because the launcher entry points at wherever the file is:
+
+```bash
+mkdir -p ~/Apps
+mv ~/Downloads/Triple-C_*_amd64.AppImage ~/Apps/
+./scripts/install-appimage.sh ~/Apps/Triple-C_0.4.17_amd64.AppImage
+```
+
+That copies the bundled icons into `~/.local/share/icons/hicolor` and writes
+`~/.local/share/applications/triple-c.desktop` pointing at the file you named.
+No sudo, nothing outside your home directory, and the AppImage itself is never
+copied or moved. To remove the entry again:
+
+```bash
+./scripts/install-appimage.sh --uninstall
+```
+
+The script rewrites the `Exec` line rather than reusing the bundled `.desktop`
+verbatim: the bundled one says `Exec=triple-c`, which resolves only inside the
+running AppImage's own mount, so a launcher entry copied straight out of the
+bundle would appear in the menu and then fail to start anything.
+
+Two follow-ups worth knowing:
+
+- **Upgrading.** The entry names one specific file. If you replace the AppImage
+  with a newer version under a different filename, re-run the script against the
+  new one. Keeping a stable name (`~/Apps/Triple-C.AppImage`) avoids this.
+- **The icon may not appear until you log out.** That is the desktop shell's
+  icon cache, not a failed install — see
+  [App Icon Missing After Installing (Linux)](#app-icon-missing-after-installing-linux).
+
 ## Prerequisites

 ### Docker
@@ -1536,3 +1594,9 @@ cp ~/.claude.json ~/.claude.json.bak && jq 'with_entries(select(.key | startswit
 ```

 This backs up your config and removes the corrupted marketplace entries. Claude Code will re-download them cleanly on the next startup.
+
+### App Icon Missing After Installing (Linux)
+
+If Triple-C's icon shows as generic or blank right after installing — in the app menu, taskbar, and window titlebar alike — **log out and back in.**
+
+Desktop shells (GNOME Shell, KDE Plasma) cache the list of installed apps and their resolved icons in memory when the shell starts, for performance. A freshly installed package's icon files land on disk correctly and its install hooks do rebuild the on-disk icon cache, but an already-running shell doesn't always notice — on X11 there used to be a way to soft-restart just the shell (GNOME's Alt+F2 → `r`) to force a reload, but under Wayland the shell *is* the compositor, so restarting it means ending the session. Logging out and back in starts a fresh shell that reads the current on-disk state, which picks the icon up.
@@ -418,12 +418,6 @@ triple-c/
 │       ├── build-stt.yml            # Build the STT image
 │       ├── backfill-releases.yml    # Bulk copy releases to GitHub
 │       ├── cleanup-releases.yml     # Prune old releases
-│       └── publish-aur-package.yml  # Publish triple-c-bin to the AUR (packaging/arch/)
-│
-├── packaging/
-│   └── arch/                      # AUR triple-c-bin package — see packaging/arch/README.md
-│       ├── PKGBUILD
-│       └── README.md
 │
 └── app/                           # Tauri v2 desktop application
    ├── package.json               # React, xterm.js, zustand, tailwindcss
@@ -8,6 +8,41 @@ version = "2.0.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "320119579fcad9c21884f5c4861d16174d0e06250625266f50fe6898340abefa"

+[[package]]
+name = "aead"
+version = "0.5.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d122413f284cf2d62fb1b7db97e02edb8cda96d769b16e443a4f6195e35662b0"
+dependencies = [
+ "crypto-common",
+ "generic-array",
+]
+
+[[package]]
+name = "aes"
+version = "0.8.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b169f7a6d4742236a0a00c541b845991d0ac43e546831af1249753ab4c3aa3a0"
+dependencies = [
+ "cfg-if",
+ "cipher",
+ "cpufeatures",
+]
+
+[[package]]
+name = "aes-gcm"
+version = "0.10.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "831010a0f742e1209b3bcea8fab6a8e149051ba6099432c8cb2cc117dec3ead1"
+dependencies = [
+ "aead",
+ "aes",
+ "cipher",
+ "ctr",
+ "ghash",
+ "subtle",
+]
+
 [[package]]
 name = "aho-corasick"
 version = "1.1.4"
@@ -47,6 +82,18 @@ version = "1.0.102"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "7f202df86484c868dbad7eaa557ef785d5c66295e41b460ef922eca0723b842c"

+[[package]]
+name = "argon2"
+version = "0.5.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3c3610892ee6e0cbce8ae2700349fcf8f98adb0dbfbee85aec3c9179d29cc072"
+dependencies = [
+ "base64ct",
+ "blake2",
+ "cpufeatures",
+ "password-hash",
+]
+
 [[package]]
 name = "async-broadcast"
 version = "0.7.2"
@@ -280,6 +327,12 @@ version = "0.22.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "72b3254f16251a8381aa12e40e3c4d2f0199f8c6508fbecb9d91f575e0fbb8c6"

+[[package]]
+name = "base64ct"
+version = "1.8.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2af50177e190e07a26ab74f8b1efbfe2ef87da2116221318cb1c2e82baf7de06"
+
 [[package]]
 name = "bit-set"
 version = "0.8.0"
@@ -310,6 +363,15 @@ dependencies = [
 "serde_core",
 ]

+[[package]]
+name = "blake2"
+version = "0.10.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "46502ad458c9a52b69d4d4d32775c788b7a1b85e8bc9d482d92250fc0e3f8efe"
+dependencies = [
+ "digest",
+]
+
 [[package]]
 name = "block-buffer"
 version = "0.10.4"
@@ -569,6 +631,16 @@ dependencies = [
 "windows-link 0.2.1",
 ]

+[[package]]
+name = "cipher"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "773f3b9af64447d2ce9850330c473515014aa235e6a783b02db81ff39e4a3dad"
+dependencies = [
+ "crypto-common",
+ "inout",
+]
+
 [[package]]
 name = "combine"
 version = "4.6.7"
@@ -694,6 +766,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "78c8292055d1c1df0cce5d180393dc8cce0abec0a7102adb6c7b1eef6016d60a"
 dependencies = [
 "generic-array",
+ "rand_core 0.6.4",
 "typenum",
 ]

@@ -753,6 +826,15 @@ version = "0.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "52560adf09603e58c9a7ee1fe1dcb95a16927b17c127f0ac02d6e768a0e25bc1"

+[[package]]
+name = "ctr"
+version = "0.9.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0369ee1ad671834580515889b80f2ea915f23b8be8d0daa4bbaf2ac5c7590835"
+dependencies = [
+ "cipher",
+]
+
 [[package]]
 name = "darling"
 version = "0.20.11"
@@ -923,6 +1005,7 @@ checksum = "9ed9a281f7bc9b7576e61468ba615a66a5c8cfdff42420a70aa82701a3b1e292"
 dependencies = [
 "block-buffer",
 "crypto-common",
+ "subtle",
 ]

 [[package]]
@@ -1550,6 +1633,16 @@ dependencies = [
 "syn 2.0.117",
 ]

+[[package]]
+name = "ghash"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f0d8a4362ccb29cb0b265253fb0a2728f592895ee6854fd9bc13f2ffda266ff1"
+dependencies = [
+ "opaque-debug",
+ "polyval",
+]
+
 [[package]]
 name = "gio"
 version = "0.18.4"
@@ -2114,6 +2207,15 @@ dependencies = [
 "cfb",
 ]

+[[package]]
+name = "inout"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "879f10e63c20629ecabbb64a8010319738c66a5cd0c29b02d63d272b03751d01"
+dependencies = [
+ "generic-array",
+]
+
 [[package]]
 name = "ipnet"
 version = "2.11.0"
@@ -2831,6 +2933,12 @@ version = "1.21.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "42f5e15c9953c5e4ccceeb2e7382a716482c34515315f7b03532b8b4e8393d2d"

+[[package]]
+name = "opaque-debug"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c08d65885ee38876c4f86fa503fb49d7b507c2b62552df7c70b2fce627e06381"
+
 [[package]]
 name = "open"
 version = "5.3.3"
@@ -2913,6 +3021,17 @@ dependencies = [
 "windows-link 0.2.1",
 ]

+[[package]]
+name = "password-hash"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "346f04948ba92c43e8469c1ee6736c7563d71012b17d40745260fe106aac2166"
+dependencies = [
+ "base64ct",
+ "rand_core 0.6.4",
+ "subtle",
+]
+
 [[package]]
 name = "pathdiff"
 version = "0.2.3"
@@ -3194,6 +3313,18 @@ dependencies = [
 "windows-sys 0.61.2",
 ]

+[[package]]
+name = "polyval"
+version = "0.6.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9d1fe60d06143b2430aa532c94cfe9e29783047f06c0d7fd359a9a51b729fa25"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "opaque-debug",
+ "universal-hash",
+]
+
 [[package]]
 name = "potential_utf"
 version = "0.1.4"
@@ -5149,6 +5280,8 @@ dependencies = [
 name = "triple-c"
 version = "0.4.0"
 dependencies = [
+ "aes-gcm",
+ "argon2",
 "axum",
 "base64 0.22.1",
 "bollard",
@@ -5174,6 +5307,7 @@ dependencies = [
 "tokio",
 "tower-http",
 "uuid",
+ "zeroize",
 ]

 [[package]]
@@ -5287,6 +5421,16 @@ version = "0.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ebc1c04c71510c7f702b52b7c350734c9ff1295c464a03335b00bb84fc54f853"

+[[package]]
+name = "universal-hash"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fc1de2c688dc15305988b563c3854064043356019f97a4b46276fe734c4f07ea"
+dependencies = [
+ "crypto-common",
+ "subtle",
+]
+
 [[package]]
 name = "untrusted"
 version = "0.9.0"
@@ -36,6 +36,9 @@ tower-http = { version = "0.6", features = ["cors"] }
 base64 = "0.22"
 rand = "0.9"
 local-ip-address = "0.6"
+argon2 = "0.5"
+aes-gcm = "0.10"
+zeroize = "1"

 [dev-dependencies]
 # `test-util` (not part of tokio's `full`) lets the auto-start retry tests run
@@ -10,6 +10,7 @@ pub mod install_helper_commands;
 pub mod migration_commands;
 pub mod project_commands;
 pub mod settings_commands;
+pub mod settings_export_commands;
 pub mod stt_commands;
 pub mod terminal_commands;
 pub mod update_commands;
@@ -10,19 +10,24 @@ pub async fn get_settings(state: State<'_, AppState>) -> Result<AppSettings, Str
    Ok(state.settings_store.get())
 }

-#[tauri::command]
-pub async fn update_settings(
-    settings: AppSettings,
-    state: State<'_, AppState>,
-) -> Result<AppSettings, String> {
-    let before = state.settings_store.get();
-
+/// Everything `update_settings` refuses a save over, run against the store's
+/// *current* value and the incoming one.
+///
+/// Pulled out so a caller that does other, harder-to-undo work alongside a
+/// settings save — `settings_export_commands::apply_settings_import`
+/// restores three keychain secrets in the same command — can run this
+/// *first* and bail before touching anything, rather than discovering the
+/// rejection only when `update_settings` itself runs partway through.
+pub fn validate_settings_update(
+    before: &AppSettings,
+    incoming: &AppSettings,
+) -> Result<(), String> {
    // The global half of the same rule the project half gets in
    // `update_project`: a global custom env var is merged into every project's
    // container environment, so an unchecked name here reaches all of them.
    crate::models::validate_env_vars_update(
        &before.global_custom_env_vars,
-        &settings.global_custom_env_vars,
+        &incoming.global_custom_env_vars,
    )?;

    // The same for the two host paths this struct owns. `update_project`
@@ -40,14 +45,37 @@ pub async fn update_settings(
    crate::commands::project_commands::validate_mounted_host_path(
        "SSH key path",
        before.default_ssh_key_path.as_deref(),
-        settings.default_ssh_key_path.as_deref(),
+        incoming.default_ssh_key_path.as_deref(),
    )?;
    crate::commands::project_commands::validate_mounted_host_path(
        "CA certificate path",
        before.ca_cert_path.as_deref(),
-        settings.ca_cert_path.as_deref(),
+        incoming.ca_cert_path.as_deref(),
    )?;

+    // Third host path this struct owns, same reasoning: any project with
+    // `allow_docker_access` bind-mounts this path in as the Docker socket
+    // (`project_commands.rs`'s container creation), so an unchecked value
+    // here is a read-write bind mount of whatever it names into every such
+    // project's container.
+    crate::commands::project_commands::validate_mounted_host_path(
+        "Docker socket path",
+        before.docker_socket_path.as_deref(),
+        incoming.docker_socket_path.as_deref(),
+    )?;
+
+    Ok(())
+}
+
+#[tauri::command]
+pub async fn update_settings(
+    settings: AppSettings,
+    state: State<'_, AppState>,
+) -> Result<AppSettings, String> {
+    let before = state.settings_store.get();
+
+    validate_settings_update(&before, &settings)?;
+
    let saved = state.settings_store.update(settings)?;

    // Persisting a setting is not the same as applying it. The gateway is the
@@ -122,7 +150,10 @@ async fn reconcile_gateway(before: &GatewaySettings, after: &GatewaySettings) {
        GatewayAction::StopIfRunning => {
            log::info!("Model gateway disabled in settings — stopping the container");
            if let Err(e) = docker::gateway::stop_gateway_container().await {
-                log::error!("Failed to stop the model gateway after it was disabled: {}", e);
+                log::error!(
+                    "Failed to stop the model gateway after it was disabled: {}",
+                    e
+                );
            }
        }
        GatewayAction::RestartIfRunning => {
@@ -138,10 +169,7 @@ async fn reconcile_gateway(before: &GatewaySettings, after: &GatewaySettings) {
 }

 #[tauri::command]
-pub async fn pull_image(
-    image_name: String,
-    app_handle: tauri::AppHandle,
-) -> Result<(), String> {
+pub async fn pull_image(image_name: String, app_handle: tauri::AppHandle) -> Result<(), String> {
    use tauri::Emitter;
    docker::pull_image(&image_name, move |msg| {
        let _ = app_handle.emit("image-pull-progress", msg);
@@ -334,7 +362,10 @@ mod tests {
        let before = enabled_gateway();
        let mut after = before.clone();
        after.enabled = false;
-        assert_eq!(gateway_action(&before, &after), GatewayAction::StopIfRunning);
+        assert_eq!(
+            gateway_action(&before, &after),
+            GatewayAction::StopIfRunning
+        );
        // Still true when it was already off — a stray running container is
        // still a container that shouldn't be up.
        assert_eq!(gateway_action(&after, &after), GatewayAction::StopIfRunning);
@@ -0,0 +1,654 @@
+//! Settings export/import — see triple-c#35.
+//!
+//! Exports the *host* environment (global `AppSettings` plus the global
+//! secrets kept in the OS keychain: the shared Claude Code OAuth login and
+//! the model gateway's two keys), encrypted with a user-chosen password —
+//! see `storage::settings_crypto` for the actual cryptography. Deliberately
+//! out of scope: per-project settings, per-project secrets, and anything
+//! living in a project's Docker volumes.
+//!
+//! **The save/open dialogs are opened from Rust**, the same pattern
+//! `file_commands.rs`'s `pick_save_path`/`pick_files_to_upload` already
+//! establish and document at length: a frontend-driven dialog handing Rust a
+//! host path string is the exact shape of bug that produced this app's past
+//! criticals, so the boundary here is drawn the same place. The frontend can
+//! ask for a picker; it cannot name a host path as an *input*. `preview_
+//! settings_import` resolves the chosen path itself and remembers it
+//! (`AppState::pending_settings_import`) so `apply_settings_import` re-reads
+//! the same file without the path ever crossing back over IPC.
+//!
+//! The *decrypted payload* is not cached between preview and apply — the
+//! password the frontend passes to each call is what it already held for
+//! the first, not a fresh secret extracted from the user, but nothing here
+//! keeps the plaintext itself — export/import secrets included — around for
+//! longer than one command's execution; `apply_settings_import` re-decrypts
+//! the file rather than reusing anything `preview_settings_import` computed.
+//!
+//! **This is new attack surface**: a settings export is a file one person
+//! can hand another and ask them to import, together with a password, and
+//! `apply_settings_import` applies whatever `AppSettings` it decrypts to
+//! wholesale — see the module doc on `models::settings_export` for the
+//! `web_terminal.access_token` carve-out a review of this feature found,
+//! and treat that as the standing example of the class of thing to keep
+//! checking for here, not a one-off fixed bug.
+
+#[cfg(test)]
+use std::path::Path;
+use std::path::PathBuf;
+
+use sha2::{Digest, Sha256};
+use tauri::State;
+use tauri_plugin_dialog::DialogExt;
+use zeroize::Zeroizing;
+
+use crate::models::{
+    AppSettings, ExportedSecrets, SettingsExportPayload, SettingsImportOutcome,
+    SettingsImportPreview, SETTINGS_EXPORT_FORMAT_VERSION,
+};
+use crate::storage::{secure, settings_crypto};
+use crate::AppState;
+
+/// What `preview_settings_import` pins so `apply_settings_import` can tell
+/// whether the file it's about to re-read is the same one the user actually
+/// saw a preview of. Confirming a preview is only meaningful if it's binding
+/// on what gets applied — without this, a file replaced on disk between the
+/// two calls (this app's own stated threat model is a file shared between
+/// people, which may sit in a synced or shared directory) would decrypt and
+/// apply silently different content than what the confirmation dialog showed.
+#[derive(Debug, Clone)]
+pub struct PendingSettingsImport {
+    path: PathBuf,
+    ciphertext_hash: [u8; 32],
+}
+
+fn hash_ciphertext(data: &[u8]) -> [u8; 32] {
+    Sha256::digest(data).into()
+}
+
+const FILE_EXTENSION: &str = "triplec";
+
+/// Enforced here, not only in the export modal: the frontend's minimum is a
+/// UX nudge, but `export_settings` is the actual boundary a weak password
+/// has to cross, and Argon2id's memory-hardness buys little against an
+/// attacker who can just try a three-character password directly.
+const MIN_PASSWORD_LEN: usize = 8;
+
+fn suggested_export_name() -> String {
+    // Timestamped so exporting more than once doesn't silently overwrite an
+    // earlier file just because the save dialog defaults to the same name.
+    format!(
+        "triple-c-settings-{}.{}",
+        chrono::Utc::now().format("%Y%m%d-%H%M%S"),
+        FILE_EXTENSION
+    )
+}
+
+async fn pick_export_save_path(window: &tauri::Window, suggested: &str) -> Option<PathBuf> {
+    let (tx, rx) = tokio::sync::oneshot::channel();
+    window
+        .dialog()
+        .file()
+        .set_parent(window)
+        .set_title("Export Triple-C settings")
+        .set_file_name(suggested)
+        .add_filter("Triple-C settings export", &[FILE_EXTENSION])
+        .save_file(move |picked| {
+            let _ = tx.send(picked);
+        });
+    rx.await.ok().flatten().and_then(|p| p.into_path().ok())
+}
+
+async fn pick_import_open_path(window: &tauri::Window) -> Option<PathBuf> {
+    let (tx, rx) = tokio::sync::oneshot::channel();
+    window
+        .dialog()
+        .file()
+        .set_parent(window)
+        .set_title("Import Triple-C settings")
+        .add_filter("Triple-C settings export", &[FILE_EXTENSION])
+        .pick_file(move |picked| {
+            let _ = tx.send(picked);
+        });
+    rx.await.ok().flatten().and_then(|p| p.into_path().ok())
+}
+
+/// Gather the current global secrets, and hand back the `AppSettings` to
+/// export with the web-terminal token blanked out of it — see the module
+/// doc comment on `models::settings_export` for why that field cannot
+/// travel through `settings` like the rest of this struct.
+///
+/// A missing keychain secret reads as `None` — a keychain read failure is
+/// treated as "nothing to export" for that one entry rather than aborting
+/// the whole export, matching how the rest of this app degrades a keychain
+/// error to "absent" (`has_claude_oauth_token`, `has_gateway_api_key`)
+/// rather than surfacing it as a hard failure.
+fn split_settings_and_secrets(current: AppSettings) -> (AppSettings, ExportedSecrets) {
+    let mut settings = current;
+    let web_terminal_access_token = settings.web_terminal.access_token.take();
+
+    let secrets = ExportedSecrets {
+        claude_oauth_token: secure::get_claude_oauth_token().unwrap_or_default(),
+        gateway_api_key: secure::get_gateway_api_key().unwrap_or_default(),
+        gateway_master_key: secure::get_gateway_master_key().unwrap_or_default(),
+        web_terminal_access_token,
+    };
+
+    (settings, secrets)
+}
+
+/// Export the current global settings and secrets to a password-encrypted
+/// file. `Ok(false)` means the save dialog was dismissed — not an error, and
+/// deliberately distinguishable from one so the frontend shows nothing
+/// rather than a "failed" toast for a plain cancel.
+#[tauri::command]
+pub async fn export_settings(
+    password: String,
+    window: tauri::Window,
+    state: State<'_, AppState>,
+) -> Result<bool, String> {
+    // `.chars().count()` — Unicode scalar values, not bytes — to stay as
+    // close as this pair of languages allows to the frontend's `.length`
+    // check (UTF-16 code units); the two only diverge on astral-plane
+    // characters, which no reasonable password touches.
+    if password.chars().count() < MIN_PASSWORD_LEN {
+        return Err(format!(
+            "Use a password of at least {} characters.",
+            MIN_PASSWORD_LEN
+        ));
+    }
+
+    let Some(dest) = pick_export_save_path(&window, &suggested_export_name()).await else {
+        return Ok(false);
+    };
+
+    let (settings, secrets) = split_settings_and_secrets(state.settings_store.get());
+    if secrets.is_empty() {
+        log::info!("Exporting settings with no global secrets configured on this machine");
+    }
+
+    let payload = SettingsExportPayload {
+        format_version: SETTINGS_EXPORT_FORMAT_VERSION,
+        exported_at: chrono::Utc::now().to_rfc3339(),
+        app_version: env!("CARGO_PKG_VERSION").to_string(),
+        settings,
+        secrets,
+    };
+
+    let plaintext = Zeroizing::new(
+        serde_json::to_vec(&payload)
+            .map_err(|e| format!("Failed to prepare settings for export: {}", e))?,
+    );
+    let encrypted = settings_crypto::encrypt(&plaintext, &password)?;
+
+    std::fs::write(&dest, &encrypted).map_err(|e| format!("Failed to write export file: {}", e))?;
+
+    Ok(true)
+}
+
+/// Open a file picker, decrypt the chosen file with `password`, and return a
+/// preview (counts and presence flags only — never a secret value) for a
+/// confirmation UI. `Ok(None)` means the picker was dismissed.
+///
+/// Remembers the resolved path *and a hash of the file's ciphertext* in
+/// `AppState::pending_settings_import` for `apply_settings_import` to check
+/// against — does **not** remember the decrypted payload itself, so the
+/// password must be supplied again to actually apply it — seeing the preview
+/// is not the same as committing to it. The hash exists so it also can't be
+/// swapped out from under that commitment: `apply_settings_import` refuses to
+/// proceed if the file on disk no longer matches what was just previewed.
+#[tauri::command]
+pub async fn preview_settings_import(
+    password: String,
+    window: tauri::Window,
+    state: State<'_, AppState>,
+) -> Result<Option<SettingsImportPreview>, String> {
+    if password.is_empty() {
+        return Err("A password is required to open a settings export.".to_string());
+    }
+
+    let Some(path) = pick_import_open_path(&window).await else {
+        return Ok(None);
+    };
+
+    let encrypted = std::fs::read(&path).map_err(|e| format!("Failed to read export file: {}", e))?;
+    let payload = read_and_decrypt_bytes(&encrypted, &password)?;
+    let preview = SettingsImportPreview::from_payload(&payload);
+
+    *state.pending_settings_import.lock().await = Some(PendingSettingsImport {
+        path,
+        ciphertext_hash: hash_ciphertext(&encrypted),
+    });
+
+    Ok(Some(preview))
+}
+
+/// Apply the import a prior `preview_settings_import` call resolved a path
+/// for. Fails if no preview is pending — this is not a general "decrypt and
+/// apply this file" entry point, deliberately: seeing the preview first is
+/// required, not just encouraged, since it is the only place a user is told
+/// what an import is about to touch before it touches it. That requirement
+/// is only real if the file can't change out from under it, so this also
+/// refuses to proceed if the file's ciphertext no longer matches the hash
+/// `preview_settings_import` pinned — a file replaced on disk between the
+/// two calls (this feature's own threat model is a file shared between
+/// people, which may sit in a synced or shared directory) must not be able
+/// to apply silently different content than what the confirmation dialog
+/// showed.
+///
+/// Global settings are replaced wholesale — an import is "restore this
+/// environment," not a field-by-field merge. Global secrets are handled
+/// differently and on purpose: **only secrets actually present in the
+/// import are written**; a secret the export doesn't have is left alone on
+/// this machine rather than cleared, because an absent secret in the export
+/// means "the source machine never had this configured," not "delete this
+/// on import." A user who wants to clear a secret already has dedicated UI
+/// for that (signing out of shared auth, clearing the gateway key).
+///
+/// Order matters here, twice over.
+///
+/// First: the imported settings are **validated before any secret is
+/// written**, using the same checks `update_settings` itself runs
+/// (`settings_commands::validate_settings_update`). Restoring a secret is
+/// hard to undo unnoticed — a stale env-var-name rejection or a disallowed
+/// host path used to be caught only when `update_settings` ran, by which
+/// point the three keychain secrets below were already overwritten with the
+/// file's, each with a fresh rotation id, silently flagging every project
+/// container for recreation — while the error the user saw talked only
+/// about the rejected setting and said nothing about the credentials that
+/// had already moved. Failing this check first makes a rejected import
+/// leave nothing touched, matching what "the import failed" is supposed to
+/// mean.
+///
+/// Second, among the things that *do* get written: secrets are restored
+/// **before** the settings replace runs (which is what triggers
+/// `reconcile_gateway`), so a gateway recreation that replace provokes sees
+/// the final key material rather than racing it — restoring the other way
+/// round left a real window where the running gateway and the keychain
+/// briefly disagreed. A gateway *secret* alone (same shape, new key) is
+/// invisible to `reconcile_gateway`'s shape comparison, so this additionally
+/// nudges a running gateway container to recreate itself whenever a secret
+/// this import carried was actually written — otherwise the running
+/// container keeps serving the old key material indefinitely while every
+/// project container is handed the new one.
+///
+/// A keychain write failing is reported back rather than only logged: an
+/// import that silently restores two of three secrets but not the third
+/// must not read as unqualified success.
+///
+/// The pending import is only cleared on success. A failure here (rejected
+/// by the validation above, a stale-file mismatch, or some other error)
+/// leaves it pending so the frontend can let the user retry `apply` without
+/// making them pick the file and re-enter the password again — the
+/// preview's job was confirming *what* to import, not spending the one
+/// attempt at applying it.
+#[tauri::command]
+pub async fn apply_settings_import(
+    password: String,
+    state: State<'_, AppState>,
+) -> Result<SettingsImportOutcome, String> {
+    if password.is_empty() {
+        return Err("A password is required to import settings.".to_string());
+    }
+
+    let pending = state
+        .pending_settings_import
+        .lock()
+        .await
+        .clone()
+        .ok_or_else(|| "No import is pending — choose a file first.".to_string())?;
+
+    let encrypted = std::fs::read(&pending.path)
+        .map_err(|e| format!("Failed to read export file: {}", e))?;
+    if hash_ciphertext(&encrypted) != pending.ciphertext_hash {
+        return Err(
+            "This file changed since you reviewed it — choose it again to see an up-to-date preview."
+                .to_string(),
+        );
+    }
+    let payload = read_and_decrypt_bytes(&encrypted, &password)?;
+
+    let current = state.settings_store.get();
+
+    // The web-terminal token lives inside `AppSettings` itself rather than
+    // the keychain, so "leave an absent secret alone" has to be done by
+    // hand here: carry the destination's current token forward when the
+    // import doesn't have one, instead of letting the wholesale replace
+    // below blank it (every export writes `None` there — see
+    // `split_settings_and_secrets`).
+    let mut settings = payload.settings;
+    settings.web_terminal.access_token = non_blank(payload.secrets.web_terminal_access_token)
+        .or_else(|| current.web_terminal.access_token.clone());
+
+    crate::commands::settings_commands::validate_settings_update(&current, &settings)?;
+
+    let mut secret_restore_warnings = Vec::new();
+    let mut gateway_secret_changed = false;
+
+    if let Some(token) = non_blank(payload.secrets.claude_oauth_token) {
+        if let Err(e) = secure::store_claude_oauth_token(&token) {
+            log::warn!(
+                "Settings import: could not restore the shared Claude login: {}",
+                e
+            );
+            secret_restore_warnings
+                .push(format!("Could not restore your shared Claude login: {}", e));
+        }
+    }
+    if let Some(key) = non_blank(payload.secrets.gateway_api_key) {
+        match secure::store_gateway_api_key(&key) {
+            Ok(()) => gateway_secret_changed = true,
+            Err(e) => {
+                log::warn!(
+                    "Settings import: could not restore the gateway provider API key: {}",
+                    e
+                );
+                secret_restore_warnings.push(format!(
+                    "Could not restore the gateway provider API key: {}",
+                    e
+                ));
+            }
+        }
+    }
+    if let Some(key) = non_blank(payload.secrets.gateway_master_key) {
+        match secure::store_gateway_master_key(&key) {
+            Ok(()) => gateway_secret_changed = true,
+            Err(e) => {
+                log::warn!(
+                    "Settings import: could not restore the gateway master key: {}",
+                    e
+                );
+                secret_restore_warnings
+                    .push(format!("Could not restore the gateway master key: {}", e));
+            }
+        }
+    }
+
+    let saved =
+        crate::commands::settings_commands::update_settings(settings, state.clone()).await?;
+
+    // `reconcile_gateway` (inside `update_settings`) only reacts to a changed
+    // *shape* — port, provider, base URL, models — because that's what's
+    // rendered into the container's config. A secret changing with the shape
+    // held constant is invisible to it, so a running gateway container would
+    // otherwise keep serving the old key material forever after an import
+    // that restored a new one, while `docker::gateway`'s own fingerprint
+    // (which does include the secret rotation id) means the *next* unrelated
+    // settings save would suddenly and confusingly recreate it instead.
+    if gateway_secret_changed && saved.gateway.enabled {
+        match crate::docker::gateway::gateway_container_presence().await {
+            Ok((true, true)) => {
+                if let Err(e) = crate::docker::gateway::ensure_gateway_running(&saved.gateway).await
+                {
+                    log::error!(
+                        "Settings import: could not apply the restored gateway credentials to the running gateway container: {}",
+                        e
+                    );
+                }
+            }
+            Ok(_) => {}
+            Err(e) => log::debug!("Settings import: gateway reconcile skipped ({})", e),
+        }
+    }
+
+    state.pending_settings_import.lock().await.take();
+
+    Ok(SettingsImportOutcome {
+        settings: saved,
+        secret_restore_warnings,
+    })
+}
+
+fn non_blank(value: Option<String>) -> Option<String> {
+    value.filter(|v| !v.trim().is_empty())
+}
+
+/// Only the field `read_and_decrypt` needs before deciding whether the rest
+/// of the payload is even worth attempting to parse.
+#[derive(serde::Deserialize)]
+struct FormatVersionProbe {
+    format_version: u32,
+}
+
+/// Read and decrypt an export file at `path`, then parse it — see
+/// `read_and_decrypt_bytes` for why the format-version check runs before the
+/// full parse. Every real caller already has the file's bytes in hand by the
+/// time it needs this (`preview_settings_import`/`apply_settings_import`
+/// both hash the ciphertext first) and calls `read_and_decrypt_bytes`
+/// directly to avoid reading the file twice; this path-based wrapper only
+/// exists now for tests that don't need that.
+#[cfg(test)]
+fn read_and_decrypt(path: &Path, password: &str) -> Result<SettingsExportPayload, String> {
+    let encrypted =
+        std::fs::read(path).map_err(|e| format!("Failed to read export file: {}", e))?;
+    read_and_decrypt_bytes(&encrypted, password)
+}
+
+/// Decrypt and parse an already-read export file's bytes, checking the
+/// format version **before** attempting to deserialize the full payload.
+///
+/// That ordering is not just tidiness: a version bump that isn't
+/// deserialize-compatible (a field's type changes, not just a new
+/// `#[serde(default)]`-covered one) is exactly the case this check exists
+/// for, and parsing the full struct first would fail on the shape mismatch
+/// before the version check ever ran, surfacing a raw parse error instead
+/// of "update Triple-C" — and, more seriously, `serde_json`'s type-mismatch
+/// errors quote the offending value inline. This file is not attacker
+/// content in the usual sense (it must still decrypt under the right
+/// password), but the plaintext it decrypts to can hold a live credential,
+/// so neither error path below ever interpolates what `serde_json`
+/// actually says — only a fixed, generic message.
+fn read_and_decrypt_bytes(encrypted: &[u8], password: &str) -> Result<SettingsExportPayload, String> {
+    let plaintext = settings_crypto::decrypt(encrypted, password)?;
+
+    let probe: FormatVersionProbe = serde_json::from_slice(&plaintext)
+        .map_err(|_| "This file doesn't look like a valid settings export.".to_string())?;
+    if probe.format_version > SETTINGS_EXPORT_FORMAT_VERSION {
+        return Err(format!(
+            "This export was made by a newer version of Triple-C (format {}, this app supports up to {}). \
+             Update Triple-C before importing it.",
+            probe.format_version, SETTINGS_EXPORT_FORMAT_VERSION
+        ));
+    }
+
+    serde_json::from_slice(&plaintext).map_err(|_| {
+        "This file doesn't look like a valid settings export (unexpected shape).".to_string()
+    })
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn non_blank_treats_whitespace_only_as_absent() {
+        assert_eq!(non_blank(Some("   ".to_string())), None);
+        assert_eq!(non_blank(Some("".to_string())), None);
+        assert_eq!(non_blank(None), None);
+        assert_eq!(non_blank(Some(" a ".to_string())), Some(" a ".to_string()));
+    }
+
+    #[test]
+    fn ciphertext_hashing_is_deterministic_and_tamper_sensitive() {
+        // What `apply_settings_import` compares against the pinned hash from
+        // `preview_settings_import` to detect a file swapped out from under a
+        // pending import — this only defends anything if identical bytes
+        // always hash identically and any change to those bytes changes the
+        // hash.
+        let bytes = b"pretend this is an encrypted export file";
+        assert_eq!(hash_ciphertext(bytes), hash_ciphertext(bytes));
+
+        let mut tampered = bytes.to_vec();
+        tampered[0] ^= 0xFF;
+        assert_ne!(hash_ciphertext(bytes), hash_ciphertext(&tampered));
+    }
+
+    fn write_export(
+        dir: &std::path::Path,
+        name: &str,
+        payload: &SettingsExportPayload,
+        password: &str,
+    ) -> PathBuf {
+        write_raw_export(dir, name, &serde_json::to_value(payload).unwrap(), password)
+    }
+
+    /// Like `write_export`, but takes an arbitrary `serde_json::Value` rather
+    /// than a real `SettingsExportPayload` — for fixtures that are
+    /// deliberately not shape-compatible, which the typed helper above can't
+    /// produce at all.
+    fn write_raw_export(
+        dir: &std::path::Path,
+        name: &str,
+        value: &serde_json::Value,
+        password: &str,
+    ) -> PathBuf {
+        let plaintext = serde_json::to_vec(value).unwrap();
+        let encrypted = settings_crypto::encrypt(&plaintext, password).unwrap();
+        let path = dir.join(name);
+        std::fs::write(&path, &encrypted).unwrap();
+        path
+    }
+
+    #[test]
+    fn splitting_settings_moves_the_web_terminal_token_out_rather_than_copying_it() {
+        let mut settings = AppSettings::default();
+        settings.web_terminal.access_token = Some("super-secret-token".to_string());
+
+        let (settings, secrets) = split_settings_and_secrets(settings);
+
+        assert_eq!(settings.web_terminal.access_token, None);
+        assert_eq!(
+            secrets.web_terminal_access_token,
+            Some("super-secret-token".to_string())
+        );
+    }
+
+    #[test]
+    fn splitting_settings_with_no_token_leaves_it_absent_on_both_sides() {
+        let (settings, secrets) = split_settings_and_secrets(AppSettings::default());
+
+        assert_eq!(settings.web_terminal.access_token, None);
+        assert_eq!(secrets.web_terminal_access_token, None);
+    }
+
+    fn sample_payload(format_version: u32) -> SettingsExportPayload {
+        SettingsExportPayload {
+            format_version,
+            exported_at: "2026-08-27T00:00:00Z".to_string(),
+            app_version: "0.4.14".to_string(),
+            settings: AppSettings::default(),
+            secrets: ExportedSecrets::default(),
+        }
+    }
+
+    fn temp_dir(name: &str) -> PathBuf {
+        let dir = std::env::temp_dir().join(format!(
+            "triple-c-settings-export-test-{}-{}",
+            name,
+            uuid::Uuid::new_v4().simple()
+        ));
+        std::fs::create_dir_all(&dir).unwrap();
+        dir
+    }
+
+    #[test]
+    fn a_file_from_a_newer_format_is_refused_before_the_full_shape_is_parsed() {
+        // Shape-incompatible with the *current* `SettingsExportPayload` (a
+        // future version could easily have changed `settings` from an object
+        // to something else) as well as newer — so this only passes under
+        // the probe-first ordering. Parsing the full struct first (the old
+        // behavior) would fail on the shape mismatch and never reach the
+        // version check, producing the "unexpected shape" message instead of
+        // "newer version" / "Update Triple-C".
+        let dir = temp_dir("newer-format");
+        let path = write_raw_export(
+            &dir,
+            "export.triplec",
+            &serde_json::json!({
+                "format_version": SETTINGS_EXPORT_FORMAT_VERSION + 1,
+                "exported_at": "2026-08-27T00:00:00Z",
+                "app_version": "9.9.9",
+                "settings": "this-app-version-stores-settings-differently",
+                "secrets": {},
+            }),
+            "correct password",
+        );
+
+        let err = read_and_decrypt(&path, "correct password").unwrap_err();
+        assert!(err.contains("newer version"), "unexpected message: {}", err);
+        assert!(err.contains("Update Triple-C"));
+
+        std::fs::remove_dir_all(&dir).ok();
+    }
+
+    #[test]
+    fn a_file_at_the_current_format_is_accepted() {
+        let dir = temp_dir("current-format");
+        let path = write_export(
+            &dir,
+            "export.triplec",
+            &sample_payload(SETTINGS_EXPORT_FORMAT_VERSION),
+            "correct password",
+        );
+
+        let payload = read_and_decrypt(&path, "correct password").unwrap();
+        assert_eq!(payload.format_version, SETTINGS_EXPORT_FORMAT_VERSION);
+
+        std::fs::remove_dir_all(&dir).ok();
+    }
+
+    #[test]
+    fn a_malformed_payload_produces_a_generic_error_not_a_raw_serde_message() {
+        // A `format_version` the probe accepts, but a `settings` field of
+        // the wrong *type* rather than just a missing field — this is what
+        // makes `serde_json` produce an "invalid type: string `...`, expected
+        // struct AppSettings" error that quotes the offending value
+        // verbatim. That value here stands in for plaintext that, in a real
+        // export, could be a live credential — the assertion below is only
+        // meaningful against a fixture that actually exercises serde's
+        // value-quoting behavior, which a merely-missing-field fixture does
+        // not.
+        let dir = temp_dir("malformed");
+        let path = write_raw_export(
+            &dir,
+            "export.triplec",
+            &serde_json::json!({
+                "format_version": SETTINGS_EXPORT_FORMAT_VERSION,
+                "exported_at": "2026-08-27T00:00:00Z",
+                "app_version": "0.4.14",
+                "settings": "NOT-A-REAL-CREDENTIAL-abc123",
+                "secrets": {},
+            }),
+            "correct password",
+        );
+
+        let err = read_and_decrypt(&path, "correct password").unwrap_err();
+        assert!(
+            !err.contains("NOT-A-REAL-CREDENTIAL-abc123"),
+            "leaked plaintext into the error: {}",
+            err
+        );
+        assert!(err.contains("doesn't look like a valid settings export"));
+
+        std::fs::remove_dir_all(&dir).ok();
+    }
+
+    #[test]
+    fn the_wrong_password_is_reported_without_a_version_check_ever_running() {
+        let dir = temp_dir("wrong-password");
+        let path = write_export(
+            &dir,
+            "export.triplec",
+            &sample_payload(SETTINGS_EXPORT_FORMAT_VERSION),
+            "correct password",
+        );
+
+        let err = read_and_decrypt(&path, "wrong password").unwrap_err();
+        assert!(
+            err.contains("Wrong password"),
+            "unexpected message: {}",
+            err
+        );
+
+        std::fs::remove_dir_all(&dir).ok();
+    }
+}
@@ -29,6 +29,21 @@ pub struct AppState {
    pub auth_bridge: Arc<AuthBridgeManager>,
    pub web_terminal_server: Arc<tokio::sync::Mutex<Option<WebTerminalServer>>>,
    pub lifecycle: Arc<Lifecycle>,
+    /// The file `preview_settings_import` last decrypted successfully, held
+    /// so `apply_settings_import` can re-read and re-decrypt the same file
+    /// without the frontend ever passing a host path back to Rust as an
+    /// argument — see the doc comment on `commands::settings_export_commands`
+    /// for why that direction specifically is the one this app treats as
+    /// dangerous. Deliberately re-decrypted rather than cached in plaintext:
+    /// nothing here holds a decrypted secret in memory for longer than one
+    /// command's execution.
+    ///
+    /// Also pins a hash of the file's ciphertext at preview time, so
+    /// `apply_settings_import` can refuse to proceed if the file on disk
+    /// changed underneath the pending import — otherwise confirming a
+    /// preview is not actually binding on what gets applied.
+    pub pending_settings_import:
+        Arc<tokio::sync::Mutex<Option<commands::settings_export_commands::PendingSettingsImport>>>,
 }

 // ─────────────────────────────────────────────────────────────────────────────
@@ -222,6 +237,7 @@ pub fn run() {
            auth_bridge,
            web_terminal_server: Arc::new(tokio::sync::Mutex::new(None)),
            lifecycle,
+            pending_settings_import: Arc::new(tokio::sync::Mutex::new(None)),
        })
        .setup(move |app| {
            match tauri::image::Image::from_bytes(include_bytes!("../icons/icon.png")) {
@@ -494,6 +510,10 @@ pub fn run() {
            commands::settings_commands::inspect_ca_cert_path,
            commands::settings_commands::list_aws_profiles,
            commands::settings_commands::detect_host_timezone,
+            // Settings export/import
+            commands::settings_export_commands::export_settings,
+            commands::settings_export_commands::preview_settings_import,
+            commands::settings_export_commands::apply_settings_import,
            // Terminal
            commands::terminal_commands::open_terminal_session,
            commands::terminal_commands::terminal_input,
@@ -26,12 +26,27 @@
 /// their own init time, which happens inside the Tauri builder that
 /// function calls into, not at binary load.
 ///
-/// A user who has already set this themselves is left alone. That includes
-/// setting it to `0`, on the assumption WebKitGTK treats it as a boolean
-/// rather than presence-only — not verified against WebKitGTK's own source,
-/// so if it turns out to be presence-only, `=0` still reads as "set" here
-/// and disables DMA-BUF the same as any other value, which is at least the
-/// safe direction to be wrong in.
+/// A user who has already set this themselves is left alone — with one
+/// correction. The earlier version of this function left *any* pre-set value
+/// alone, including `0`, on the assumption WebKitGTK reads the variable as a
+/// boolean. WebKitGTK reads it as presence-only, so `WEBKIT_DISABLE_DMABUF_
+/// RENDERER=0` disabled DMA-BUF exactly like `=1` did, and there was no value
+/// at all a user could set to get the accelerated path back: the escape hatch
+/// the comment described did not exist. `0`, `false` and empty are now treated
+/// as an explicit opt-out and the variable is *removed*, which is the only
+/// thing WebKitGTK reads as "enabled". The default is unchanged — unset still
+/// means disabled on Linux, so nobody who was not deliberately overriding this
+/// sees any difference.
+///
+/// That matters more than it looks, because the trade described above is not
+/// the trade actually being made. `@xterm/addon-webgl` does not fall back to
+/// the canvas renderer here: its constructor throws only when WebGL is
+/// *absent*, and with DMA-BUF disabled WebGL is still present — served by
+/// software rasterisation. So the addon loads happily and every terminal frame
+/// is rendered on the CPU and copied, which is slower than the canvas renderer
+/// this comment assumed it would degrade to, not faster. See
+/// `terminal_gpu_rendering` in `AppSettings` for the switch that decides
+/// whether the addon is loaded at all.
 ///
 /// This env var also leaks to whatever the app spawns afterwards — notably
 /// a cold-launched default browser via the `opener` plugin's `xdg-open`
@@ -39,10 +54,77 @@
 /// URL; most non-WebKitGTK browsers ignore the variable entirely), but
 /// worth knowing before chasing the "links don't open" half of triple-c#34
 /// as a separate, unrelated cause.
+#[cfg(target_os = "linux")]
+const DMABUF_VAR: &str = "WEBKIT_DISABLE_DMABUF_RENDERER";
+
+/// What to do with `WEBKIT_DISABLE_DMABUF_RENDERER`, given whatever it is
+/// already set to. Split from the mutation so it can be tested without
+/// touching process-wide environment state from a parallel test runner.
+#[cfg(target_os = "linux")]
+#[derive(Debug, PartialEq, Eq)]
+enum DmabufAction {
+    /// Not set by the user — apply the workaround.
+    Disable,
+    /// Explicitly opted out. WebKitGTK reads presence, not value, so the only
+    /// way to express "enabled" is for the variable not to exist.
+    Remove,
+    /// Set to something meaning "disabled". Already what we want; leave it.
+    LeaveAlone,
+}
+
+#[cfg(target_os = "linux")]
+fn dmabuf_action(current: Option<&str>) -> DmabufAction {
+    match current {
+        None => DmabufAction::Disable,
+        Some(value) => match value.trim().to_ascii_lowercase().as_str() {
+            "" | "0" | "false" | "no" => DmabufAction::Remove,
+            _ => DmabufAction::LeaveAlone,
+        },
+    }
+}
+
 #[cfg(target_os = "linux")]
 fn apply_webkit_wayland_workaround() {
-    if std::env::var_os("WEBKIT_DISABLE_DMABUF_RENDERER").is_none() {
-        std::env::set_var("WEBKIT_DISABLE_DMABUF_RENDERER", "1");
+    let current = std::env::var(DMABUF_VAR).ok();
+    match dmabuf_action(current.as_deref()) {
+        DmabufAction::Disable => std::env::set_var(DMABUF_VAR, "1"),
+        DmabufAction::Remove => std::env::remove_var(DMABUF_VAR),
+        DmabufAction::LeaveAlone => {}
+    }
+}
+
+#[cfg(all(test, target_os = "linux"))]
+mod tests {
+    use super::{dmabuf_action, DmabufAction};
+
+    #[test]
+    fn unset_gets_the_workaround() {
+        assert_eq!(dmabuf_action(None), DmabufAction::Disable);
+    }
+
+    #[test]
+    fn falsey_values_opt_out_by_removing_the_variable() {
+        // The bug this replaces: these all previously read as "user set it,
+        // leave it alone", and WebKitGTK then disabled DMA-BUF anyway because
+        // it only checks presence. There was no way to ask for the GPU path.
+        for value in ["0", "false", "no", "", "  0  ", "FALSE", "No"] {
+            assert_eq!(
+                dmabuf_action(Some(value)),
+                DmabufAction::Remove,
+                "{value:?} should opt out"
+            );
+        }
+    }
+
+    #[test]
+    fn other_values_are_left_alone() {
+        for value in ["1", "true", "yes", "anything"] {
+            assert_eq!(
+                dmabuf_action(Some(value)),
+                DmabufAction::LeaveAlone,
+                "{value:?} should be left alone"
+            );
+        }
    }
 }

@@ -135,6 +135,26 @@ pub struct AppSettings {
    pub gateway: GatewaySettings,
    #[serde(default)]
    pub global_claude_code_settings: Option<ClaudeCodeSettings>,
+    /// Whether the terminal loads `@xterm/addon-webgl`.
+    ///
+    /// `None` is "auto", and auto is not the same answer on every platform.
+    /// On Linux the app disables WebKitGTK's DMA-BUF renderer at startup (see
+    /// `apply_webkit_wayland_workaround` in `main.rs`, and triple-c#34), which
+    /// does not remove WebGL — it leaves it backed by software rasterisation.
+    /// The addon therefore loads successfully and then renders every frame on
+    /// the CPU, which is slower than the canvas renderer it would otherwise
+    /// have fallen back to. So auto means enabled on macOS and Windows, and
+    /// disabled on Linux.
+    ///
+    /// `Some(true)` / `Some(false)` force it either way on any platform. A
+    /// Linux user running X11, or one whose driver stack is unaffected, can
+    /// turn it back on; anyone seeing terminal lag can turn it off without
+    /// waiting for a release. Deliberately `Option<bool>` rather than `bool`:
+    /// the zero value has to mean "we choose", not "off", or every existing
+    /// settings file would silently pin the answer at whatever the default was
+    /// the day it was written.
+    #[serde(default)]
+    pub terminal_gpu_rendering: Option<bool>,
 }

 fn default_stt_model() -> String {
@@ -226,6 +246,7 @@ impl Default for AppSettings {
            stt: SttSettings::default(),
            gateway: GatewaySettings::default(),
            global_claude_code_settings: None,
+            terminal_gpu_rendering: None,
        }
    }
 }
@@ -3,6 +3,7 @@ pub mod container_config;
 pub mod app_settings;
 pub mod gateway_settings;
 pub mod migration;
+pub mod settings_export;
 pub mod update_info;

 pub use project::*;
@@ -10,4 +11,5 @@ pub use container_config::*;
 pub use app_settings::*;
 pub use gateway_settings::*;
 pub use migration::*;
+pub use settings_export::*;
 pub use update_info::*;
@@ -0,0 +1,366 @@
+//! Settings export/import — see triple-c#35.
+//!
+//! `SettingsExportPayload` is the whole plaintext export before encryption
+//! and after decryption (see `storage::settings_crypto`). It bundles
+//! `AppSettings` — with one field carved out, see below — with the global
+//! secrets that live in the OS keychain instead: the shared Claude Code
+//! OAuth login and the model gateway's two keys. Per-project settings,
+//! per-project secrets, and anything living in a project's Docker volumes
+//! are deliberately out of scope: this exports the *host* environment, not
+//! any one project's.
+//!
+//! **`AppSettings` is not entirely the non-secret shape it looks like.**
+//! `WebTerminalSettings::access_token` is a live bearer credential for a
+//! server that binds every interface, stored as a plain field on the
+//! struct that is otherwise safe to treat as config. A review of this
+//! feature caught it: exporting `AppSettings` wholesale would have carried
+//! that token along as if it were as inert as a port number, and — worse —
+//! importing it would apply `web_terminal.enabled` and the token together
+//! with no more warning than any other setting, letting a crafted export
+//! silently stand up a LAN-listening terminal server with an
+//! attacker-known token on the next launch. `export_settings` /
+//! `apply_settings_import` blank this field out of the `settings` they
+//! read from and write to, and it travels only through
+//! [`ExportedSecrets::web_terminal_access_token`] instead, with the same
+//! "only overwrite what the import actually has" treatment as the other
+//! three secrets.
+
+use serde::{Deserialize, Serialize};
+
+use super::{AppSettings, ImageSource};
+
+/// Bumped when the shape of [`SettingsExportPayload`] changes in a way that
+/// isn't just an additive, `#[serde(default)]`-covered field — e.g. if a
+/// field is ever removed or its meaning changes. `apply_settings_import`
+/// checks this before touching anything.
+pub const SETTINGS_EXPORT_FORMAT_VERSION: u32 = 1;
+
+/// The global secrets bundled into an export. Deliberately a separate struct
+/// from `AppSettings`: these live in the OS keychain, never in
+/// `settings.json`, and — outside of this export/import flow — the values
+/// themselves never cross into the frontend; see the doc comments on
+/// `storage::secure::get_gateway_api_key` and
+/// `commands::settings_export_commands` for why that boundary matters here
+/// too.
+#[derive(Debug, Clone, Serialize, Deserialize, Default)]
+pub struct ExportedSecrets {
+    #[serde(default)]
+    pub claude_oauth_token: Option<String>,
+    #[serde(default)]
+    pub gateway_api_key: Option<String>,
+    #[serde(default)]
+    pub gateway_master_key: Option<String>,
+    /// See the module doc comment — this is `AppSettings::web_terminal
+    /// .access_token`, carved out because it is a live bearer credential,
+    /// not config, despite living on a struct that is otherwise safe to
+    /// export wholesale.
+    #[serde(default)]
+    pub web_terminal_access_token: Option<String>,
+}
+
+impl ExportedSecrets {
+    pub fn is_empty(&self) -> bool {
+        let blank = |s: &Option<String>| s.as_deref().is_none_or(|v| v.trim().is_empty());
+        blank(&self.claude_oauth_token)
+            && blank(&self.gateway_api_key)
+            && blank(&self.gateway_master_key)
+            && blank(&self.web_terminal_access_token)
+    }
+}
+
+/// What `apply_settings_import` hands back: the settings that were actually
+/// saved, plus a human-readable note for each keychain secret this import
+/// carried but could not be restored. A keychain write failing partway
+/// through must not read as unqualified success just because the settings
+/// half of the import went through.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct SettingsImportOutcome {
+    pub settings: AppSettings,
+    #[serde(default)]
+    pub secret_restore_warnings: Vec<String>,
+}
+
+/// The full plaintext payload — this is what gets encrypted on export and
+/// what decryption recovers on import. Never written to disk unencrypted;
+/// see `storage::settings_crypto`.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct SettingsExportPayload {
+    pub format_version: u32,
+    /// RFC3339. Purely informational — shown in the import preview so a user
+    /// picking between a few old export files has something to go on.
+    pub exported_at: String,
+    /// The exporting app's `CARGO_PKG_VERSION`. Also informational: every
+    /// field below already round-trips through `#[serde(default)]`-covered
+    /// `AppSettings`, so an older or newer export still deserializes; this is
+    /// for a human to notice "this is from a much older version" if an import
+    /// ever looks wrong, not something the code branches on.
+    pub app_version: String,
+    pub settings: AppSettings,
+    #[serde(default)]
+    pub secrets: ExportedSecrets,
+}
+
+/// What `preview_settings_import` hands the frontend before anything is
+/// applied — counts and presence flags only, **never** a secret value itself,
+/// so this type is safe to return across the IPC boundary and render
+/// directly. The confirmation UI is built from this.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct SettingsImportPreview {
+    pub exported_at: String,
+    pub app_version: String,
+    pub custom_env_var_count: usize,
+    pub gateway_model_count: usize,
+    pub has_claude_code_settings: bool,
+    pub has_claude_oauth_token: bool,
+    pub has_gateway_api_key: bool,
+    pub has_gateway_master_key: bool,
+    pub has_web_terminal_access_token: bool,
+    /// Whether the imported settings turn the web terminal on. Named
+    /// separately from the token above: `enabled` and the token are two
+    /// different fields, either can be true without the other, and
+    /// "this import turns on a service that listens on your network" is
+    /// exactly the kind of change a wholesale settings replace must not
+    /// bury in a generic "settings replaced" line — see the module doc
+    /// comment on why this field exists at all.
+    pub enables_web_terminal: bool,
+    /// Non-blank custom base URLs the import would set, so a redirect of
+    /// model traffic to somewhere other than the usual provider is visible
+    /// at import time rather than discovered later. These are endpoints, not
+    /// secrets — safe to show verbatim, unlike everything above.
+    #[serde(default)]
+    pub ollama_base_url: Option<String>,
+    #[serde(default)]
+    pub llamacpp_base_url: Option<String>,
+    #[serde(default)]
+    pub openai_compatible_base_url: Option<String>,
+    #[serde(default)]
+    pub gateway_api_base: Option<String>,
+    /// Whether the import sets a custom Docker image, and its name if so —
+    /// disclosed for the same reason as the base URLs above, and arguably
+    /// more sharply: this is the image *every* project container is created
+    /// from (`models::container_config::resolve_image_name`), so a crafted
+    /// export pointing it at an attacker-controlled image is a path to
+    /// running arbitrary code with whatever a project's containers are
+    /// allowed to reach (the Docker socket, an SSH key, project files) —
+    /// not merely a redirected API endpoint.
+    #[serde(default)]
+    pub image_source: ImageSource,
+    #[serde(default)]
+    pub custom_image_name: Option<String>,
+}
+
+/// A cap on how much of a decrypted, not-yet-trusted string gets echoed back
+/// into a preview a user reads and a UI renders without truncation of its
+/// own. Applied to every field above that carries free-form text straight
+/// from the import file rather than a count or a boolean — a base URL or an
+/// image name a hostile export author controls has had no validation done
+/// on it yet at preview time, and nothing stops it from being pathological
+/// (embedded control characters, or long enough to blow out the confirmation
+/// dialog and push the security warnings below it off screen).
+const MAX_PREVIEW_STRING_LEN: usize = 100;
+
+fn sanitize_for_preview(value: &str) -> String {
+    let cleaned: String = value.chars().filter(|c| !c.is_control()).collect();
+    let trimmed = cleaned.trim();
+    if trimmed.chars().count() > MAX_PREVIEW_STRING_LEN {
+        let truncated: String = trimmed.chars().take(MAX_PREVIEW_STRING_LEN).collect();
+        format!("{}…", truncated)
+    } else {
+        trimmed.to_string()
+    }
+}
+
+impl SettingsImportPreview {
+    pub fn from_payload(payload: &SettingsExportPayload) -> Self {
+        let non_blank = |s: &Option<String>| s.as_deref().is_some_and(|v| !v.trim().is_empty());
+        let sanitized_non_blank = |s: &Option<String>| {
+            s.as_deref()
+                .map(sanitize_for_preview)
+                .filter(|v| !v.is_empty())
+        };
+        Self {
+            exported_at: payload.exported_at.clone(),
+            app_version: payload.app_version.clone(),
+            custom_env_var_count: payload.settings.global_custom_env_vars.len(),
+            gateway_model_count: payload.settings.gateway.models.len(),
+            has_claude_code_settings: payload.settings.global_claude_code_settings.is_some(),
+            has_claude_oauth_token: non_blank(&payload.secrets.claude_oauth_token),
+            has_gateway_api_key: non_blank(&payload.secrets.gateway_api_key),
+            has_gateway_master_key: non_blank(&payload.secrets.gateway_master_key),
+            has_web_terminal_access_token: non_blank(&payload.secrets.web_terminal_access_token),
+            enables_web_terminal: payload.settings.web_terminal.enabled,
+            ollama_base_url: sanitized_non_blank(&payload.settings.global_ollama.base_url),
+            llamacpp_base_url: sanitized_non_blank(&payload.settings.global_llamacpp.base_url),
+            openai_compatible_base_url: sanitized_non_blank(
+                &payload.settings.global_openai_compatible.base_url,
+            ),
+            gateway_api_base: sanitized_non_blank(&payload.settings.gateway.api_base),
+            image_source: payload.settings.image_source.clone(),
+            custom_image_name: sanitized_non_blank(&payload.settings.custom_image_name),
+        }
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use crate::models::AppSettings;
+
+    fn payload_with(secrets: ExportedSecrets) -> SettingsExportPayload {
+        let settings = AppSettings {
+            global_custom_env_vars: vec![
+                crate::models::EnvVar {
+                    key: "A".to_string(),
+                    value: "1".to_string(),
+                },
+                crate::models::EnvVar {
+                    key: "B".to_string(),
+                    value: "2".to_string(),
+                },
+            ],
+            ..AppSettings::default()
+        };
+        SettingsExportPayload {
+            format_version: SETTINGS_EXPORT_FORMAT_VERSION,
+            exported_at: "2026-08-27T00:00:00Z".to_string(),
+            app_version: "0.4.14".to_string(),
+            settings,
+            secrets,
+        }
+    }
+
+    #[test]
+    fn the_preview_never_carries_a_secret_value() {
+        let payload = payload_with(ExportedSecrets {
+            claude_oauth_token: Some("sk-super-secret-token".to_string()),
+            gateway_api_key: Some("sk-another-secret".to_string()),
+            gateway_master_key: Some("sk-triple-c-yet-another".to_string()),
+            web_terminal_access_token: Some("wt-super-secret-token".to_string()),
+        });
+        let preview = SettingsImportPreview::from_payload(&payload);
+        let serialized = serde_json::to_string(&preview).unwrap();
+
+        assert!(!serialized.contains("sk-super-secret-token"));
+        assert!(!serialized.contains("sk-another-secret"));
+        assert!(!serialized.contains("sk-triple-c-yet-another"));
+        assert!(!serialized.contains("wt-super-secret-token"));
+        assert!(preview.has_claude_oauth_token);
+        assert!(preview.has_gateway_api_key);
+        assert!(preview.has_gateway_master_key);
+        assert!(preview.has_web_terminal_access_token);
+    }
+
+    #[test]
+    fn a_blank_secret_reads_as_absent_in_the_preview() {
+        // A keychain entry that exists but holds only whitespace must not
+        // read as "present" — same "blank counts as absent" rule the
+        // keychain layer itself applies when storing these.
+        let payload = payload_with(ExportedSecrets {
+            claude_oauth_token: Some("   ".to_string()),
+            gateway_api_key: None,
+            gateway_master_key: None,
+            web_terminal_access_token: Some("   ".to_string()),
+        });
+        let preview = SettingsImportPreview::from_payload(&payload);
+        assert!(!preview.has_claude_oauth_token);
+        assert!(!preview.has_gateway_api_key);
+        assert!(!preview.has_gateway_master_key);
+        assert!(!preview.has_web_terminal_access_token);
+    }
+
+    #[test]
+    fn enabling_the_web_terminal_is_surfaced_regardless_of_whether_a_token_came_with_it() {
+        // `enabled` and the token are independent fields — a crafted export
+        // could set one without the other, and both are worth a user's
+        // attention: this is the field that exists specifically so "this
+        // import turns on a service that listens on your network" cannot
+        // hide inside a generic "settings replaced" summary.
+        let mut payload = payload_with(ExportedSecrets::default());
+        payload.settings.web_terminal.enabled = true;
+        let preview = SettingsImportPreview::from_payload(&payload);
+        assert!(preview.enables_web_terminal);
+        assert!(!preview.has_web_terminal_access_token);
+    }
+
+    #[test]
+    fn custom_base_urls_are_surfaced_but_blank_ones_read_as_absent() {
+        let mut payload = payload_with(ExportedSecrets::default());
+        payload.settings.global_ollama.base_url = Some("http://attacker.example:11434".to_string());
+        payload.settings.global_llamacpp.base_url = Some("   ".to_string());
+        payload.settings.gateway.api_base = Some("https://gateway.example/v1".to_string());
+
+        let preview = SettingsImportPreview::from_payload(&payload);
+        assert_eq!(
+            preview.ollama_base_url.as_deref(),
+            Some("http://attacker.example:11434")
+        );
+        assert_eq!(preview.llamacpp_base_url, None);
+        assert_eq!(preview.openai_compatible_base_url, None);
+        assert_eq!(
+            preview.gateway_api_base.as_deref(),
+            Some("https://gateway.example/v1")
+        );
+    }
+
+    #[test]
+    fn counts_reflect_the_real_settings() {
+        let payload = payload_with(ExportedSecrets::default());
+        let preview = SettingsImportPreview::from_payload(&payload);
+        assert_eq!(preview.custom_env_var_count, 2);
+    }
+
+    #[test]
+    fn an_empty_secrets_bundle_reports_itself_as_empty() {
+        assert!(ExportedSecrets::default().is_empty());
+        assert!(!ExportedSecrets {
+            claude_oauth_token: Some("x".to_string()),
+            ..Default::default()
+        }
+        .is_empty());
+    }
+
+    #[test]
+    fn a_secrets_bundle_holding_only_whitespace_still_reports_itself_as_empty() {
+        // Matches the "blank counts as absent" rule every other consumer of
+        // these fields applies (`has_claude_oauth_token` and friends above) —
+        // a keychain entry that exists but holds only whitespace carries
+        // nothing usable, so the export-time "nothing to export" log line
+        // must still fire for it.
+        assert!(ExportedSecrets {
+            claude_oauth_token: Some("   ".to_string()),
+            ..Default::default()
+        }
+        .is_empty());
+    }
+
+    #[test]
+    fn a_custom_docker_image_is_surfaced() {
+        let mut payload = payload_with(ExportedSecrets::default());
+        payload.settings.image_source = crate::models::ImageSource::Custom;
+        payload.settings.custom_image_name = Some("ghcr.io/attacker/triple-c:latest".to_string());
+
+        let preview = SettingsImportPreview::from_payload(&payload);
+        assert_eq!(preview.image_source, crate::models::ImageSource::Custom);
+        assert_eq!(
+            preview.custom_image_name.as_deref(),
+            Some("ghcr.io/attacker/triple-c:latest")
+        );
+    }
+
+    #[test]
+    fn preview_strings_are_stripped_of_control_characters_and_capped_in_length() {
+        let mut payload = payload_with(ExportedSecrets::default());
+        payload.settings.global_ollama.base_url =
+            Some(format!("http://example.test/{}\u{0007}bell", "x".repeat(200)));
+
+        let preview = SettingsImportPreview::from_payload(&payload);
+        let shown = preview.ollama_base_url.expect("non-blank base url");
+        assert!(!shown.contains('\u{0007}'), "control character leaked into the preview");
+        // +1 for the trailing ellipsis appended when truncated.
+        assert!(
+            shown.chars().count() <= MAX_PREVIEW_STRING_LEN + 1,
+            "preview string was not capped: {} chars",
+            shown.chars().count()
+        );
+    }
+}
@@ -2,6 +2,7 @@ pub mod migration_store;
 pub mod pending_cleanup;
 pub mod projects_store;
 pub mod secure;
+pub mod settings_crypto;
 pub mod settings_store;

 #[allow(unused_imports)]
@@ -321,28 +321,52 @@ pub fn delete_gateway_api_key() -> Result<(), String> {
 /// only enforces auth when a master key is configured, so Triple-C always
 /// configures one.
 pub fn get_or_create_gateway_master_key() -> Result<String, String> {
-    if let Some(existing) = read_entry(GATEWAY_MASTER_KEY_SERVICE, "the gateway master key")? {
-        if !existing.trim().is_empty() {
-            return Ok(existing);
-        }
+    if let Some(existing) = get_gateway_master_key()? {
+        return Ok(existing);
    }
    regenerate_gateway_master_key()
 }

+/// Read the gateway master key without minting one if none exists yet.
+/// Distinct from [`get_or_create_gateway_master_key`], which mints as a side
+/// effect the read half of that function must not have — settings export
+/// (triple-c#35) needs "is there one, and if so what is it", not "make sure
+/// one exists".
+pub fn get_gateway_master_key() -> Result<Option<String>, String> {
+    Ok(read_entry(GATEWAY_MASTER_KEY_SERVICE, "the gateway master key")?
+        .filter(|k| !k.trim().is_empty()))
+}
+
 /// Mint a new gateway master key, invalidating the old one. Projects using the
 /// previous value must be updated.
 pub fn regenerate_gateway_master_key() -> Result<String, String> {
    // LiteLLM requires the master key to start with `sk-`.
    let key = format!("sk-triple-c-{}", uuid::Uuid::new_v4().simple());
+    store_gateway_master_key(&key)?;
+    Ok(key)
+}
+
+/// Store an exact given gateway master key, replacing any previous one.
+///
+/// Distinct from [`regenerate_gateway_master_key`], which always mints a
+/// fresh random value: this exists for settings import (triple-c#35), where
+/// restoring the *same* key an export captured is the point — projects on
+/// the destination machine may not exist yet, but a project migrated or
+/// re-added later that still has the old key pasted into its config must
+/// keep working against it. Blank input is rejected rather than silently
+/// stored, matching every other `store_*` function in this module.
+pub fn store_gateway_master_key(key: &str) -> Result<(), String> {
+    if key.trim().is_empty() {
+        return Err("Refusing to store an empty gateway master key.".to_string());
+    }

    let entry = keyring::Entry::new(GATEWAY_MASTER_KEY_SERVICE, KEYCHAIN_ACCOUNT)
        .map_err(|e| format!("Keyring error: {}", e))?;
    entry
-        .set_password(&key)
+        .set_password(key.trim())
        .map_err(|e| format!("Failed to store the gateway master key: {}", e))?;

-    bump_gateway_secret_version()?;
-    Ok(key)
+    bump_gateway_secret_version()
 }


@@ -0,0 +1,184 @@
+//! Password-based encryption for the settings export/import file — see
+//! triple-c#35.
+//!
+//! The exported payload can carry live credentials (the shared Claude OAuth
+//! token, the gateway provider/master keys — see
+//! `commands::settings_export_commands`), so this is not encryption for its
+//! own sake; a wrong or missing key here is a real credential leak, not a
+//! cosmetic bug. Argon2id derives a 256-bit key from the password (memory-
+//! hard, meaningfully resistant to GPU/ASIC brute-forcing in a way PBKDF2 at
+//! any reasonable iteration count is not), and AES-256-GCM is what actually
+//! encrypts — authenticated, so a wrong password is detected by a failed tag
+//! check rather than producing silent garbage.
+//!
+//! File format: `MAGIC (4 bytes) | salt (16 bytes) | nonce (12 bytes) |
+//! ciphertext+tag`. The salt and nonce are not secret — they are written in
+//! the clear right here, on purpose. The salt's only job is to make two
+//! exports with the same password derive different keys (defeats a
+//! precomputed-table attack against the password alone); the nonce's job is
+//! GCM's requirement that a (key, nonce) pair never repeat. Both hold
+//! because a fresh random value is drawn for each, on every call to
+//! [`encrypt`].
+//!
+//! The whole header (magic + salt + nonce) is passed to AES-GCM as
+//! associated data, not just placed alongside the ciphertext — free to do,
+//! and it makes tampering with any header byte fail the same authentication
+//! check the ciphertext gets, by construction rather than as a side effect
+//! of the salt/nonce also feeding key derivation and the cipher.
+
+use aes_gcm::aead::{Aead, KeyInit, Payload};
+use aes_gcm::{Aes256Gcm, Nonce};
+use argon2::{Algorithm, Argon2, Params, Version};
+use rand::RngCore;
+use zeroize::Zeroizing;
+
+/// Identifies the file as a Triple-C settings export and pins the format —
+/// a change to the salt/nonce lengths or the KDF/cipher choice below needs a
+/// new magic value, not a silent reinterpretation of old bytes.
+const MAGIC: &[u8; 4] = b"TCX1";
+const SALT_LEN: usize = 16;
+const NONCE_LEN: usize = 12;
+const KEY_LEN: usize = 32;
+const HEADER_LEN: usize = MAGIC.len() + SALT_LEN + NONCE_LEN;
+
+/// Argon2id parameters: memory cost in KiB, time cost (iterations),
+/// parallelism. `(19 MiB, 2, 1)` is OWASP's documented minimum recommendation
+/// for Argon2id — deliberately heavier than a login-flow KDF would use, since
+/// this runs once per export/import rather than on every request, so trading
+/// roughly a second of wall time for real brute-force resistance costs
+/// nothing a user would notice.
+fn argon2_params() -> Params {
+    Params::new(19 * 1024, 2, 1, Some(KEY_LEN)).expect("hardcoded Argon2 params are valid")
+}
+
+/// The derived key is wrapped in `Zeroizing` so it is overwritten with zeros
+/// when it drops rather than left in freed memory for whatever reuses that
+/// stack slot next — cheap insurance (`zeroize` is already in the dependency
+/// tree via `aes-gcm`) for material that exists only to decrypt live
+/// credentials.
+fn derive_key(password: &str, salt: &[u8]) -> Result<Zeroizing<[u8; KEY_LEN]>, String> {
+    let argon2 = Argon2::new(Algorithm::Argon2id, Version::V0x13, argon2_params());
+    let mut key = Zeroizing::new([0u8; KEY_LEN]);
+    argon2
+        .hash_password_into(password.as_bytes(), salt, &mut *key)
+        .map_err(|e| format!("Failed to derive encryption key: {}", e))?;
+    Ok(key)
+}
+
+/// Encrypt `plaintext` with a key derived from `password`. Returns the whole
+/// file's bytes (header + ciphertext) — see the module doc for the layout.
+pub fn encrypt(plaintext: &[u8], password: &str) -> Result<Vec<u8>, String> {
+    let mut salt = [0u8; SALT_LEN];
+    rand::rng().fill_bytes(&mut salt);
+    let key = derive_key(password, &salt)?;
+
+    let mut nonce_bytes = [0u8; NONCE_LEN];
+    rand::rng().fill_bytes(&mut nonce_bytes);
+    let nonce = Nonce::from_slice(&nonce_bytes);
+
+    let mut header = Vec::with_capacity(HEADER_LEN);
+    header.extend_from_slice(MAGIC);
+    header.extend_from_slice(&salt);
+    header.extend_from_slice(&nonce_bytes);
+
+    let cipher = Aes256Gcm::new_from_slice(&*key)
+        .map_err(|e| format!("Failed to initialize cipher: {}", e))?;
+    // The header (magic + salt + nonce) is authenticated as associated data
+    // even though none of it is secret: it costs nothing extra here, and it
+    // means tampering with any header byte is caught by the same tag check
+    // that already covers the ciphertext, by construction rather than as a
+    // side effect of the header also feeding key/nonce derivation.
+    let ciphertext = cipher
+        .encrypt(nonce, Payload { msg: plaintext, aad: &header })
+        .map_err(|e| format!("Encryption failed: {}", e))?;
+
+    let mut out = header;
+    out.extend_from_slice(&ciphertext);
+    Ok(out)
+}
+
+/// Decrypt a file produced by [`encrypt`]. The one error this returns for a
+/// wrong password is deliberately generic ("wrong password, or the file is
+/// corrupted") rather than distinguishing the two: GCM's authentication tag
+/// fails to verify for the wrong key on essentially any ciphertext, so there
+/// is no reliable way to tell "wrong password" from "corrupted file" apart,
+/// and guessing would be worse than saying so.
+///
+/// Returns `Zeroizing<Vec<u8>>` rather than a plain `Vec<u8>` — the plaintext
+/// this recovers is the whole settings-plus-secrets payload, so it gets the
+/// same "wipe it when it drops" treatment as the derived key in
+/// [`derive_key`].
+pub fn decrypt(data: &[u8], password: &str) -> Result<Zeroizing<Vec<u8>>, String> {
+    if data.len() < HEADER_LEN {
+        return Err("This does not look like a Triple-C settings export (file too short).".to_string());
+    }
+    if &data[..MAGIC.len()] != MAGIC {
+        return Err("This does not look like a Triple-C settings export (unrecognized file).".to_string());
+    }
+    let header = &data[..HEADER_LEN];
+    let salt = &data[MAGIC.len()..MAGIC.len() + SALT_LEN];
+    let nonce_bytes = &data[MAGIC.len() + SALT_LEN..HEADER_LEN];
+    let ciphertext = &data[HEADER_LEN..];
+
+    let key = derive_key(password, salt)?;
+    let cipher = Aes256Gcm::new_from_slice(&*key)
+        .map_err(|e| format!("Failed to initialize cipher: {}", e))?;
+    let nonce = Nonce::from_slice(nonce_bytes);
+    cipher
+        .decrypt(nonce, Payload { msg: ciphertext, aad: header })
+        .map(Zeroizing::new)
+        .map_err(|_| "Wrong password, or the file is corrupted.".to_string())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn a_round_trip_with_the_right_password_recovers_the_plaintext() {
+        let plaintext = b"{\"settings\": \"whatever\"}";
+        let encrypted = encrypt(plaintext, "correct horse battery staple").unwrap();
+        let decrypted = decrypt(&encrypted, "correct horse battery staple").unwrap();
+        assert_eq!(&*decrypted, plaintext);
+    }
+
+    #[test]
+    fn the_wrong_password_fails_rather_than_returning_garbage() {
+        let encrypted = encrypt(b"secret payload", "correct password").unwrap();
+        let result = decrypt(&encrypted, "wrong password");
+        assert!(result.is_err(), "decrypting with the wrong password must fail, not silently succeed");
+    }
+
+    #[test]
+    fn two_exports_of_the_same_plaintext_and_password_produce_different_files() {
+        // If this ever failed it would mean the salt or nonce stopped being
+        // randomized — either one repeating is a real security regression
+        // (a fixed salt lets an attacker precompute against the password
+        // alone; a repeated (key, nonce) pair breaks GCM's guarantees
+        // outright), not just a cosmetic one.
+        let a = encrypt(b"same plaintext", "same password").unwrap();
+        let b = encrypt(b"same plaintext", "same password").unwrap();
+        assert_ne!(a, b, "two independent exports must not be byte-identical");
+    }
+
+    #[test]
+    fn corrupting_a_single_byte_of_ciphertext_is_detected() {
+        let mut encrypted = encrypt(b"tamper-evident payload", "a password").unwrap();
+        let last = encrypted.len() - 1;
+        encrypted[last] ^= 0xFF;
+        assert!(decrypt(&encrypted, "a password").is_err());
+    }
+
+    #[test]
+    fn a_file_that_is_too_short_is_rejected_cleanly_not_by_panicking() {
+        assert!(decrypt(b"short", "any password").is_err());
+        assert!(decrypt(b"", "any password").is_err());
+    }
+
+    #[test]
+    fn a_file_with_the_wrong_magic_is_rejected() {
+        let mut encrypted = encrypt(b"payload", "password").unwrap();
+        encrypted[0] = b'X';
+        assert!(decrypt(&encrypted, "password").is_err());
+    }
+}
@@ -0,0 +1,118 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { render, screen, fireEvent, waitFor, act } from "@testing-library/react";
+import AddProjectDialog from "./AddProjectDialog";
+
+const add = vi.fn();
+
+vi.mock("../../hooks/useProjects", () => ({
+  useProjects: () => ({ add }),
+}));
+
+vi.mock("@tauri-apps/plugin-dialog", () => ({
+  open: vi.fn(async () => null),
+}));
+
+/** A promise whose resolution this test controls, so `loading` can be held open. */
+function deferred() {
+  let resolve!: (v: unknown) => void;
+  const promise = new Promise((r) => {
+    resolve = r;
+  });
+  return { promise, resolve };
+}
+
+function fillValidForm() {
+  fireEvent.change(screen.getByLabelText("Project name"), {
+    target: { value: "my-project" },
+  });
+  fireEvent.change(screen.getByLabelText("Folder 1 host path"), {
+    target: { value: "/home/user/my-project" },
+  });
+}
+
+function submitButton() {
+  return screen.getByRole("button", { name: /Add Project|Adding/ });
+}
+
+describe("AddProjectDialog", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it("adds the project with the name and folder entered", async () => {
+    add.mockResolvedValue({ id: "p1" });
+    const onClose = vi.fn();
+    render(<AddProjectDialog onClose={onClose} />);
+    fillValidForm();
+    fireEvent.click(submitButton());
+    await waitFor(() =>
+      expect(add).toHaveBeenCalledWith("my-project", [
+        { host_path: "/home/user/my-project", mount_name: "my-project" },
+      ]),
+    );
+    await waitFor(() => expect(onClose).toHaveBeenCalled());
+  });
+
+  it("keeps the submit button announced, and explains why, while adding", async () => {
+    const { promise, resolve } = deferred();
+    add.mockReturnValue(promise);
+    render(<AddProjectDialog onClose={vi.fn()} />);
+    fillValidForm();
+    fireEvent.click(submitButton());
+
+    // Native `disabled` would remove the button from the accessibility tree
+    // exactly when it has something to say.
+    await waitFor(() =>
+      expect(submitButton()).toHaveAttribute("aria-disabled", "true"),
+    );
+    expect(submitButton()).not.toBeDisabled();
+    expect(submitButton()).toHaveAccessibleDescription(/being added/i);
+
+    await act(async () => resolve({ id: "p1" }));
+  });
+
+  it("ignores clicks and Enter/Space on the submit button while adding", async () => {
+    const { promise, resolve } = deferred();
+    add.mockReturnValue(promise);
+    render(<AddProjectDialog onClose={vi.fn()} />);
+    fillValidForm();
+    fireEvent.click(submitButton());
+    await waitFor(() =>
+      expect(submitButton()).toHaveAttribute("aria-disabled", "true"),
+    );
+
+    fireEvent.click(submitButton());
+    fireEvent.keyDown(submitButton(), { key: "Enter" });
+    fireEvent.keyDown(submitButton(), { key: " " });
+    expect(add).toHaveBeenCalledTimes(1);
+
+    await act(async () => resolve({ id: "p1" }));
+  });
+
+  it("ignores a form submit raised from elsewhere while adding", async () => {
+    const { promise, resolve } = deferred();
+    add.mockReturnValue(promise);
+    render(<AddProjectDialog onClose={vi.fn()} />);
+    fillValidForm();
+    fireEvent.click(submitButton());
+    await waitFor(() =>
+      expect(submitButton()).toHaveAttribute("aria-disabled", "true"),
+    );
+
+    // Enter in a text field submits a form regardless of the submit button's
+    // state, so the handler has to guard itself too.
+    // Modal portals to document.body, so the form is not under `container`.
+    const form = document.querySelector("form");
+    expect(form).not.toBeNull();
+    fireEvent.submit(form!);
+    expect(add).toHaveBeenCalledTimes(1);
+
+    await act(async () => resolve({ id: "p1" }));
+  });
+
+  it("leaves the submit button plainly available when idle", () => {
+    render(<AddProjectDialog onClose={vi.fn()} />);
+    expect(submitButton()).not.toHaveAttribute("aria-disabled");
+    expect(submitButton()).toHaveAccessibleDescription("");
+  });
+});
@@ -55,6 +55,10 @@ export default function AddProjectDialog({ onClose }: Props) {

  const handleSubmit = async (e?: React.FormEvent) => {
    if (e) e.preventDefault();
+    // The submit button is `aria-disabled` rather than `disabled` while an add
+    // is in flight, and Enter inside a text field submits the form without
+    // touching the button at all. Both routes end here, so the guard does too.
+    if (loading) return;
    if (!name.trim()) {
      setError("Project name is required");
      return;
@@ -97,7 +101,19 @@ export default function AddProjectDialog({ onClose }: Props) {
          <Button size="md" variant="ghost" onClick={onClose}>
            Cancel
          </Button>
-          <Button size="md" variant="primary" type="submit" form={formId} disabled={loading}>
+          <Button
+            size="md"
+            variant="primary"
+            type="submit"
+            form={formId}
+            unavailable={loading}
+            unavailableReason="The project is being added. Wait for it to finish."
+            title={
+              loading
+                ? "The project is being added. Wait for it to finish."
+                : undefined
+            }
+          >
            {loading ? "Adding…" : "Add Project"}
          </Button>
        </>
@@ -122,14 +122,6 @@ describe("ProjectRow", () => {
  });

  it("only allows opening a terminal while the container runs", () => {
-    const { unmount } = render(<ProjectRow project={baseProject} />);
-    expect(
-      screen.getByRole("button", {
-        name: "Open a Claude terminal for Test Project",
-      }),
-    ).toBeDisabled();
-    unmount();
-
    render(<ProjectRow project={{ ...baseProject, status: "running" }} />);
    fireEvent.click(
      screen.getByRole("button", {
@@ -139,6 +131,38 @@ describe("ProjectRow", () => {
    expect(mockOpenClaudeTerminal).toHaveBeenCalled();
  });

+  it("keeps the terminal button announced, and explains why, while stopped", () => {
+    render(<ProjectRow project={baseProject} />);
+    const button = screen.getByRole("button", {
+      name: "Open a Claude terminal for Test Project",
+    });
+    // Native `disabled` would drop the button out of the accessibility tree
+    // and out of the tab order, taking the reason with it.
+    expect(button).not.toBeDisabled();
+    expect(button).toHaveAttribute("aria-disabled", "true");
+    expect(button).toHaveAccessibleDescription(/is not running/i);
+  });
+
+  it("ignores clicks and Enter/Space on the terminal button while stopped", () => {
+    render(<ProjectRow project={baseProject} />);
+    const button = screen.getByRole("button", {
+      name: "Open a Claude terminal for Test Project",
+    });
+    fireEvent.click(button);
+    fireEvent.keyDown(button, { key: "Enter" });
+    fireEvent.keyDown(button, { key: " " });
+    expect(mockOpenClaudeTerminal).not.toHaveBeenCalled();
+  });
+
+  it("drops aria-disabled once the container is running", () => {
+    render(<ProjectRow project={{ ...baseProject, status: "running" }} />);
+    const button = screen.getByRole("button", {
+      name: "Open a Claude terminal for Test Project",
+    });
+    expect(button).not.toHaveAttribute("aria-disabled");
+    expect(button).not.toHaveAccessibleDescription(/is not running/i);
+  });
+
  it("shows container progress inline rather than in a blocking modal", () => {
    setStore({ containerProgress: { "test-1": "Pulling image…" } });
    render(<ProjectRow project={{ ...baseProject, status: "starting" }} />);
@@ -3,6 +3,7 @@ import type { Project } from "../../lib/types";
 import { useAppState, homeTabKey } from "../../store/appState";
 import { useProjectActions } from "../../hooks/useProjectActions";
 import { ProjectStatusIndicator } from "../ui/StatusIndicator";
+import { useUnavailable } from "../ui/unavailable";

 interface Props {
  project: Project;
@@ -31,6 +32,15 @@ export default function ProjectRow({ project }: Props) {
  const isTransitioning =
    project.status === "starting" || project.status === "stopping";

+  // A terminal needs a running container. Saying so out loud beats a `disabled`
+  // attribute that hides the button — and the reason — from anyone not using a
+  // mouse and eyes.
+  const terminal = useUnavailable({
+    unavailable: !isRunning,
+    reason: `${project.name} is not running. Start it to open a terminal.`,
+    onClick: () => openClaudeTerminal(),
+  });
+
  return (
    <div
      className={`group relative px-2 py-1.5 rounded-[var(--radius-control)] transition-colors min-w-0 overflow-hidden ${
@@ -113,11 +123,14 @@ export default function ProjectRow({ project }: Props) {
        </button>
        <button
          type="button"
-          disabled={!isRunning}
-          onClick={() => openClaudeTerminal()}
-          title={`Open a Claude terminal for ${project.name}`}
+          {...terminal.controlProps}
+          title={
+            isRunning
+              ? `Open a Claude terminal for ${project.name}`
+              : `${project.name} is not running. Start it to open a terminal.`
+          }
          aria-label={`Open a Claude terminal for ${project.name}`}
-          className="w-6 h-6 flex items-center justify-center rounded-[var(--radius-control)] text-[var(--text-secondary)] hover:text-[var(--text-primary)] hover:bg-[var(--bg-primary)] disabled:text-[var(--text-disabled)] transition-colors"
+          className="w-6 h-6 flex items-center justify-center rounded-[var(--radius-control)] text-[var(--text-secondary)] hover:text-[var(--text-primary)] hover:bg-[var(--bg-primary)] disabled:text-[var(--text-disabled)] aria-disabled:text-[var(--text-disabled)] aria-disabled:hover:text-[var(--text-disabled)] aria-disabled:hover:bg-transparent aria-disabled:cursor-not-allowed transition-colors"
        >
          <svg
            className="w-3.5 h-3.5"
@@ -134,6 +147,7 @@ export default function ProjectRow({ project }: Props) {
            <line x1="13" y1="15" x2="17" y2="15" />
          </svg>
        </button>
+        {terminal.reasonNode}
      </div>
    </div>
  );
@@ -0,0 +1,72 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { fireEvent, render, screen, waitFor } from "@testing-library/react";
+import ExportSettingsModal from "./ExportSettingsModal";
+
+const exportSettings = vi.fn();
+
+vi.mock("../../lib/tauri-commands", () => ({
+  exportSettings: (password: string) => exportSettings(password),
+}));
+
+beforeEach(() => {
+  vi.clearAllMocks();
+});
+
+function fillPasswords(password: string, confirm: string) {
+  fireEvent.change(screen.getByLabelText("Password"), { target: { value: password } });
+  fireEvent.change(screen.getByLabelText("Confirm password"), { target: { value: confirm } });
+}
+
+describe("ExportSettingsModal", () => {
+  it("keeps the submit button disabled until the passwords are long enough and match", () => {
+    render(<ExportSettingsModal onClose={vi.fn()} />);
+    const submit = screen.getByRole("button", { name: /choose where to save/i });
+    expect(submit).toBeDisabled();
+
+    fillPasswords("short", "short");
+    expect(submit).toBeDisabled();
+    expect(screen.getByText(/use at least 8 characters/i)).toBeInTheDocument();
+
+    fillPasswords("longenoughpassword", "different");
+    expect(submit).toBeDisabled();
+    expect(screen.getByText(/don't match/i)).toBeInTheDocument();
+
+    fillPasswords("longenoughpassword", "longenoughpassword");
+    expect(submit).not.toBeDisabled();
+  });
+
+  it("exports with the entered password and shows success", async () => {
+    exportSettings.mockResolvedValue(true);
+    render(<ExportSettingsModal onClose={vi.fn()} />);
+
+    fillPasswords("longenoughpassword", "longenoughpassword");
+    fireEvent.click(screen.getByRole("button", { name: /choose where to save/i }));
+
+    await waitFor(() => expect(exportSettings).toHaveBeenCalledWith("longenoughpassword"));
+    await waitFor(() => expect(screen.getByText(/settings exported/i)).toBeInTheDocument());
+  });
+
+  it("closes quietly when the save dialog is dismissed", async () => {
+    exportSettings.mockResolvedValue(false);
+    const onClose = vi.fn();
+    render(<ExportSettingsModal onClose={onClose} />);
+
+    fillPasswords("longenoughpassword", "longenoughpassword");
+    fireEvent.click(screen.getByRole("button", { name: /choose where to save/i }));
+
+    await waitFor(() => expect(onClose).toHaveBeenCalled());
+    expect(screen.queryByText(/settings exported/i)).not.toBeInTheDocument();
+  });
+
+  it("shows an error rather than closing when the export fails", async () => {
+    exportSettings.mockRejectedValue("Disk is full");
+    const onClose = vi.fn();
+    render(<ExportSettingsModal onClose={onClose} />);
+
+    fillPasswords("longenoughpassword", "longenoughpassword");
+    fireEvent.click(screen.getByRole("button", { name: /choose where to save/i }));
+
+    await waitFor(() => expect(screen.getByText("Disk is full")).toBeInTheDocument());
+    expect(onClose).not.toHaveBeenCalled();
+  });
+});
@@ -0,0 +1,119 @@
+import { useState } from "react";
+import Modal from "../ui/Modal";
+import Button from "../ui/Button";
+import Field, { inputClass } from "../ui/Field";
+import { exportSettings } from "../../lib/tauri-commands";
+
+interface Props {
+  onClose: () => void;
+}
+
+const MIN_PASSWORD_LENGTH = 8;
+
+/**
+ * Password entry for exporting global settings. The save dialog itself opens
+ * from Rust once a password is confirmed here — see the doc comment on
+ * `commands::settings_export_commands` for why the host path never
+ * round-trips through this component.
+ */
+export default function ExportSettingsModal({ onClose }: Props) {
+  const [password, setPassword] = useState("");
+  const [confirmPassword, setConfirmPassword] = useState("");
+  const [busy, setBusy] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+  const [done, setDone] = useState(false);
+
+  const mismatch = confirmPassword.length > 0 && password !== confirmPassword;
+  const tooShort = password.length > 0 && password.length < MIN_PASSWORD_LENGTH;
+  const canSubmit = password.length >= MIN_PASSWORD_LENGTH && password === confirmPassword;
+
+  const handleExport = async () => {
+    setError(null);
+    setBusy(true);
+    try {
+      const saved = await exportSettings(password);
+      if (saved) setDone(true);
+      // `false` means the save dialog was dismissed — close quietly, same as
+      // if the user had cancelled the modal itself.
+      else onClose();
+    } catch (e) {
+      setError(String(e));
+    } finally {
+      setBusy(false);
+    }
+  };
+
+  return (
+    <Modal
+      title="Export settings"
+      description="Saves your global settings and any stored credentials (a shared Claude login, gateway keys) to one encrypted file. Project-specific settings and container data are not included."
+      widthClassName="w-[28rem]"
+      dismissible={!busy}
+      onClose={onClose}
+      footer={
+        done ? (
+          <Button size="md" variant="primary" onClick={onClose}>
+            Done
+          </Button>
+        ) : (
+          <>
+            <Button size="md" variant="ghost" onClick={onClose} disabled={busy}>
+              Cancel
+            </Button>
+            <Button
+              size="md"
+              variant="primary"
+              onClick={() => void handleExport()}
+              disabled={!canSubmit || busy}
+            >
+              {busy ? "Exporting…" : "Choose where to save…"}
+            </Button>
+          </>
+        )
+      }
+    >
+      {done ? (
+        <p className="text-[13px] text-[var(--success)]">
+          Settings exported. Keep the password somewhere safe — there is no way to recover
+          the file without it.
+        </p>
+      ) : (
+        <div className="space-y-3">
+          <Field label="Password" hint={`At least ${MIN_PASSWORD_LENGTH} characters. You'll need this exact password to import the file later.`}>
+            {(id) => (
+              <input
+                id={id}
+                type="password"
+                autoComplete="new-password"
+                value={password}
+                onChange={(e) => setPassword(e.target.value)}
+                disabled={busy}
+                className={inputClass}
+              />
+            )}
+          </Field>
+          <Field label="Confirm password">
+            {(id) => (
+              <input
+                id={id}
+                type="password"
+                autoComplete="new-password"
+                value={confirmPassword}
+                onChange={(e) => setConfirmPassword(e.target.value)}
+                disabled={busy}
+                className={inputClass}
+              />
+            )}
+          </Field>
+          {tooShort && (
+            <p className="text-xs text-[var(--error)]">
+              Use at least {MIN_PASSWORD_LENGTH} characters.
+            </p>
+          )}
+          {mismatch && <p className="text-xs text-[var(--error)]">Passwords don't match.</p>}
+          {error && <p className="text-xs text-[var(--error)]">{error}</p>}
+        </div>
+      )}
+    </Modal>
+  );
+}
@@ -0,0 +1,145 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { fireEvent, render, screen, waitFor } from "@testing-library/react";
+import ImportSettingsModal from "./ImportSettingsModal";
+import type { AppSettings, SettingsImportOutcome, SettingsImportPreview } from "../../lib/types";
+
+const previewSettingsImport = vi.fn();
+const applySettingsImport = vi.fn();
+
+vi.mock("../../lib/tauri-commands", () => ({
+  previewSettingsImport: (password: string) => previewSettingsImport(password),
+  applySettingsImport: (password: string) => applySettingsImport(password),
+}));
+
+beforeEach(() => {
+  vi.clearAllMocks();
+});
+
+const samplePreview: SettingsImportPreview = {
+  exported_at: "2026-08-27T00:00:00Z",
+  app_version: "0.4.14",
+  custom_env_var_count: 2,
+  gateway_model_count: 0,
+  has_claude_code_settings: false,
+  has_claude_oauth_token: true,
+  has_gateway_api_key: false,
+  has_gateway_master_key: false,
+  has_web_terminal_access_token: false,
+  enables_web_terminal: false,
+  ollama_base_url: null,
+  llamacpp_base_url: null,
+  openai_compatible_base_url: null,
+  gateway_api_base: null,
+  image_source: "registry",
+  custom_image_name: null,
+};
+
+function outcome(settings: AppSettings, secretRestoreWarnings: string[] = []): SettingsImportOutcome {
+  return { settings, secret_restore_warnings: secretRestoreWarnings };
+}
+
+describe("ImportSettingsModal", () => {
+  it("keeps 'Choose file' disabled until a password is entered", () => {
+    render(<ImportSettingsModal onClose={vi.fn()} onImported={vi.fn()} />);
+    expect(screen.getByRole("button", { name: /choose file/i })).toBeDisabled();
+
+    fireEvent.change(screen.getByLabelText("Password"), { target: { value: "hunter2" } });
+    expect(screen.getByRole("button", { name: /choose file/i })).not.toBeDisabled();
+  });
+
+  it("shows the preview and confirms with the same password used to open it", async () => {
+    previewSettingsImport.mockResolvedValue(samplePreview);
+    applySettingsImport.mockResolvedValue(outcome({} as AppSettings));
+    const onImported = vi.fn();
+    render(<ImportSettingsModal onClose={vi.fn()} onImported={onImported} />);
+
+    fireEvent.change(screen.getByLabelText("Password"), { target: { value: "hunter2" } });
+    fireEvent.click(screen.getByRole("button", { name: /choose file/i }));
+
+    await waitFor(() => expect(previewSettingsImport).toHaveBeenCalledWith("hunter2"));
+    expect(await screen.findByText(/2 global custom env vars/i)).toBeInTheDocument();
+    expect(screen.getByText(/your shared claude login/i)).toBeInTheDocument();
+
+    fireEvent.click(screen.getByRole("button", { name: /^import$/i }));
+    await waitFor(() => expect(applySettingsImport).toHaveBeenCalledWith("hunter2"));
+    await waitFor(() => expect(onImported).toHaveBeenCalledWith({}));
+    expect(await screen.findByText(/settings imported/i)).toBeInTheDocument();
+  });
+
+  it("shows a distinct warning when the import would enable the web terminal", async () => {
+    previewSettingsImport.mockResolvedValue({ ...samplePreview, enables_web_terminal: true });
+    render(<ImportSettingsModal onClose={vi.fn()} onImported={vi.fn()} />);
+
+    fireEvent.change(screen.getByLabelText("Password"), { target: { value: "hunter2" } });
+    fireEvent.click(screen.getByRole("button", { name: /choose file/i }));
+
+    expect(await screen.findByText(/enables the remote web terminal/i)).toBeInTheDocument();
+  });
+
+  it("warns about a custom Docker image every time, not just on change", async () => {
+    previewSettingsImport.mockResolvedValue({
+      ...samplePreview,
+      image_source: "custom",
+      custom_image_name: "ghcr.io/attacker/triple-c:latest",
+    });
+    render(<ImportSettingsModal onClose={vi.fn()} onImported={vi.fn()} />);
+
+    fireEvent.change(screen.getByLabelText("Password"), { target: { value: "hunter2" } });
+    fireEvent.click(screen.getByRole("button", { name: /choose file/i }));
+
+    expect(
+      await screen.findByText(/custom docker image: ghcr\.io\/attacker\/triple-c:latest/i),
+    ).toBeInTheDocument();
+  });
+
+  it("shows a secret-restore warning alongside success rather than hiding it", async () => {
+    previewSettingsImport.mockResolvedValue(samplePreview);
+    applySettingsImport.mockResolvedValue(
+      outcome({} as AppSettings, ["Could not restore the gateway master key: keychain locked"]),
+    );
+    render(<ImportSettingsModal onClose={vi.fn()} onImported={vi.fn()} />);
+
+    fireEvent.change(screen.getByLabelText("Password"), { target: { value: "hunter2" } });
+    fireEvent.click(screen.getByRole("button", { name: /choose file/i }));
+    await screen.findByText(/2 global custom env vars/i);
+
+    fireEvent.click(screen.getByRole("button", { name: /^import$/i }));
+    expect(await screen.findByText(/settings imported/i)).toBeInTheDocument();
+    expect(await screen.findByText(/could not restore the gateway master key/i)).toBeInTheDocument();
+  });
+
+  it("closes quietly when the file picker is dismissed", async () => {
+    previewSettingsImport.mockResolvedValue(null);
+    const onClose = vi.fn();
+    render(<ImportSettingsModal onClose={onClose} onImported={vi.fn()} />);
+
+    fireEvent.change(screen.getByLabelText("Password"), { target: { value: "hunter2" } });
+    fireEvent.click(screen.getByRole("button", { name: /choose file/i }));
+
+    await waitFor(() => expect(onClose).toHaveBeenCalled());
+  });
+
+  it("shows an error when the password is wrong rather than a blank preview", async () => {
+    previewSettingsImport.mockRejectedValue("Wrong password, or the file is corrupted.");
+    render(<ImportSettingsModal onClose={vi.fn()} onImported={vi.fn()} />);
+
+    fireEvent.change(screen.getByLabelText("Password"), { target: { value: "wrong" } });
+    fireEvent.click(screen.getByRole("button", { name: /choose file/i }));
+
+    expect(await screen.findByText(/wrong password, or the file is corrupted/i)).toBeInTheDocument();
+  });
+
+  it("shows an error if applying the import fails, without claiming success", async () => {
+    previewSettingsImport.mockResolvedValue(samplePreview);
+    applySettingsImport.mockRejectedValue("Keychain write failed");
+    render(<ImportSettingsModal onClose={vi.fn()} onImported={vi.fn()} />);
+
+    fireEvent.change(screen.getByLabelText("Password"), { target: { value: "hunter2" } });
+    fireEvent.click(screen.getByRole("button", { name: /choose file/i }));
+    await screen.findByText(/2 global custom env vars/i);
+
+    fireEvent.click(screen.getByRole("button", { name: /^import$/i }));
+    expect(await screen.findByText("Keychain write failed")).toBeInTheDocument();
+    expect(screen.queryByText(/settings imported/i)).not.toBeInTheDocument();
+  });
+});
@@ -0,0 +1,166 @@
+import { useState } from "react";
+import Modal from "../ui/Modal";
+import Button from "../ui/Button";
+import Field, { inputClass } from "../ui/Field";
+import { applySettingsImport, previewSettingsImport } from "../../lib/tauri-commands";
+import { describeImport, describeImportWarnings } from "../../lib/settingsImportPreview";
+import type { AppSettings, SettingsImportPreview } from "../../lib/types";
+
+interface Props {
+  onClose: () => void;
+  /** Fired once the import is actually applied, so the caller can refresh
+   *  whatever reads settings from the store. */
+  onImported: (settings: AppSettings) => void;
+}
+
+/**
+ * Two phases: enter the password and pick the file (backend resolves the
+ * file dialog itself — see `commands::settings_export_commands`), then
+ * confirm a preview before anything is actually applied. The same password
+ * is reused for the second call rather than asking again; nothing about
+ * that call needs a fresh secret; the backend just doesn't cache the
+ * *decrypted payload* between the two.
+ */
+export default function ImportSettingsModal({ onClose, onImported }: Props) {
+  const [password, setPassword] = useState("");
+  const [busy, setBusy] = useState(false);
+  const [error, setError] = useState<string | null>(null);
+  const [preview, setPreview] = useState<SettingsImportPreview | null>(null);
+  const [applied, setApplied] = useState(false);
+  const [secretWarnings, setSecretWarnings] = useState<string[]>([]);
+
+  const handleChooseFile = async () => {
+    setError(null);
+    setBusy(true);
+    try {
+      const result = await previewSettingsImport(password);
+      if (result) setPreview(result);
+      else onClose(); // File picker dismissed.
+    } catch (e) {
+      setError(String(e));
+    } finally {
+      setBusy(false);
+    }
+  };
+
+  const handleConfirm = async () => {
+    setError(null);
+    setBusy(true);
+    try {
+      const outcome = await applySettingsImport(password);
+      setApplied(true);
+      setSecretWarnings(outcome.secret_restore_warnings);
+      onImported(outcome.settings);
+    } catch (e) {
+      setError(String(e));
+    } finally {
+      setBusy(false);
+    }
+  };
+
+  return (
+    <Modal
+      title="Import settings"
+      description={
+        preview
+          ? "Review what this file will change before applying it."
+          : "Choose a Triple-C settings export and enter the password it was created with."
+      }
+      widthClassName="w-[28rem]"
+      dismissible={!busy}
+      onClose={onClose}
+      footer={
+        applied ? (
+          <Button size="md" variant="primary" onClick={onClose}>
+            Done
+          </Button>
+        ) : preview ? (
+          <>
+            <Button size="md" variant="ghost" onClick={onClose} disabled={busy}>
+              Cancel
+            </Button>
+            <Button size="md" variant="primary" onClick={() => void handleConfirm()} disabled={busy}>
+              {busy ? "Importing…" : "Import"}
+            </Button>
+          </>
+        ) : (
+          <>
+            <Button size="md" variant="ghost" onClick={onClose} disabled={busy}>
+              Cancel
+            </Button>
+            <Button
+              size="md"
+              variant="primary"
+              onClick={() => void handleChooseFile()}
+              disabled={!password || busy}
+            >
+              {busy ? "Opening…" : "Choose file…"}
+            </Button>
+          </>
+        )
+      }
+    >
+      {applied ? (
+        <div className="space-y-2">
+          <p className="text-[13px] text-[var(--success)]">Settings imported.</p>
+          {secretWarnings.map((warning) => (
+            <p
+              key={warning}
+              className="px-2.5 py-2 text-xs text-[var(--error)] bg-[var(--error-muted)] border border-[var(--error)]/40 rounded-[var(--radius-control)] leading-snug"
+            >
+              {warning}
+            </p>
+          ))}
+        </div>
+      ) : preview ? (
+        <div className="space-y-3">
+          <p className="text-xs text-[var(--text-secondary)]">
+            Exported {new Date(preview.exported_at).toLocaleString()} from Triple-C{" "}
+            {preview.app_version}.
+          </p>
+          {/* Warnings render before the replace list, deliberately: the list
+           *  below can run long, and the one thing here that most needs to
+           *  stay above the fold while scrolling is "this turns on a
+           *  network-listening service" or "this runs a different image" —
+           *  not a bullet buried among ordinary settings. */}
+          {describeImportWarnings(preview).map((warning) => (
+            <p
+              key={warning}
+              className="px-2.5 py-2 text-xs text-[var(--warning)] bg-[var(--warning-muted)] border border-[var(--warning)]/40 rounded-[var(--radius-control)] leading-snug break-all"
+            >
+              {warning}
+            </p>
+          ))}
+          <div>
+            <p className="text-[13px] font-medium text-[var(--text-primary)]">This will replace:</p>
+            <ul className="mt-1 list-disc pl-4 text-[13px] text-[var(--text-secondary)] space-y-0.5">
+              {describeImport(preview).map((item) => (
+                <li key={item} className="break-all">
+                  {item}
+                </li>
+              ))}
+            </ul>
+          </div>
+          {error && <p className="text-xs text-[var(--error)]">{error}</p>}
+        </div>
+      ) : (
+        <div className="space-y-3">
+          <Field label="Password">
+            {(id) => (
+              <input
+                id={id}
+                type="password"
+                autoComplete="current-password"
+                value={password}
+                onChange={(e) => setPassword(e.target.value)}
+                disabled={busy}
+                className={inputClass}
+              />
+            )}
+          </Field>
+          {error && <p className="text-xs text-[var(--error)]">{error}</p>}
+        </div>
+      )}
+    </Modal>
+  );
+}
@@ -15,13 +15,17 @@ import type { EnvVar } from "../../lib/types";
 import Tooltip from "../ui/Tooltip";
 import AccordionSection from "../ui/AccordionSection";
 import Toggle from "../ui/Toggle";
+import SegmentedControl from "../ui/SegmentedControl";
+import { resolveTerminalGpuRendering } from "../../lib/terminalRenderer";
 import WebTerminalSettings from "./WebTerminalSettings";
 import SttSettings from "./SttSettings";
 import SharedAuthSettings from "./SharedAuthSettings";
 import CertificateSettings from "./CertificateSettings";
+import ExportSettingsModal from "./ExportSettingsModal";
+import ImportSettingsModal from "./ImportSettingsModal";

 export default function SettingsPanel() {
-  const { appSettings, saveSettings } = useSettings();
+  const { appSettings, saveSettings, setAppSettings } = useSettings();
  const { appVersion, imageUpdateInfo, checkForUpdates, checkImageUpdate } = useUpdates();
  const [globalInstructions, setGlobalInstructions] = useState(appSettings?.global_claude_instructions ?? "");
  const [globalEnvVars, setGlobalEnvVars] = useState<EnvVar[]>(appSettings?.global_custom_env_vars ?? []);
@@ -33,6 +37,8 @@ export default function SettingsPanel() {
  const [showInstructionsModal, setShowInstructionsModal] = useState(false);
  const [showEnvVarsModal, setShowEnvVarsModal] = useState(false);
  const [showClaudeCodeSettingsModal, setShowClaudeCodeSettingsModal] = useState(false);
+  const [showExportModal, setShowExportModal] = useState(false);
+  const [showImportModal, setShowImportModal] = useState(false);

  // Sync local state when appSettings change
  useEffect(() => {
@@ -63,6 +69,14 @@ export default function SettingsPanel() {
    }
  };

+  const handleGpuRenderingChange = async (value: "auto" | "on" | "off") => {
+    if (!appSettings) return;
+    await saveSettings({
+      ...appSettings,
+      terminal_gpu_rendering: value === "auto" ? null : value === "on",
+    });
+  };
+
  const handleAutoCheckToggle = async () => {
    if (!appSettings) return;
    await saveSettings({ ...appSettings, auto_check_updates: !appSettings.auto_check_updates });
@@ -238,6 +252,45 @@ export default function SettingsPanel() {
        <SttSettings />
      </AccordionSection>

+      <AccordionSection id="terminal" title="Terminal" defaultOpen={false}>
+        <div className="space-y-2">
+          <label className="text-xs text-[var(--text-secondary)]">GPU rendering</label>
+          <SegmentedControl
+            label="Terminal GPU rendering"
+            value={
+              appSettings?.terminal_gpu_rendering == null
+                ? "auto"
+                : appSettings.terminal_gpu_rendering
+                  ? "on"
+                  : "off"
+            }
+            onChange={handleGpuRenderingChange}
+            segments={[
+              {
+                value: "auto",
+                label: "Auto",
+                hint: resolveTerminalGpuRendering(null, navigator.userAgent)
+                  ? "On for this platform."
+                  : "Off on Linux — the DMA-BUF workaround leaves WebGL on software rendering, which is slower than the canvas renderer.",
+              },
+              {
+                value: "on",
+                label: "On",
+                hint: "Always load the WebGL renderer.",
+              },
+              {
+                value: "off",
+                label: "Off",
+                hint: "Always use xterm's canvas renderer. Try this if typing feels laggy.",
+              },
+            ]}
+          />
+          <p className="text-xs text-[var(--text-secondary)]">
+            Takes effect when a terminal tab is next switched to.
+          </p>
+        </div>
+      </AccordionSection>
+
      <AccordionSection id="updates" title="Updates" defaultOpen={false}>
        <div className="space-y-2">
          {appVersion && (
@@ -269,6 +322,39 @@ export default function SettingsPanel() {
        </div>
      </AccordionSection>

+      <AccordionSection id="backup" title="Backup" defaultOpen={false}>
+        <div className="space-y-2">
+          <p className="text-xs text-[var(--text-secondary)] leading-snug">
+            Export your global settings and stored credentials (a shared Claude login,
+            gateway keys) to one password-encrypted file, or restore them on a new machine.
+            Project-specific settings and container data are never included.
+          </p>
+          <div className="flex gap-2">
+            <button
+              onClick={() => setShowExportModal(true)}
+              className="px-3 py-1.5 text-xs bg-[var(--bg-primary)] border border-[var(--border-color)] rounded hover:bg-[var(--border-color)] transition-colors"
+            >
+              Export settings…
+            </button>
+            <button
+              onClick={() => setShowImportModal(true)}
+              className="px-3 py-1.5 text-xs bg-[var(--bg-primary)] border border-[var(--border-color)] rounded hover:bg-[var(--border-color)] transition-colors"
+            >
+              Import settings…
+            </button>
+          </div>
+        </div>
+      </AccordionSection>
+
+      {showExportModal && <ExportSettingsModal onClose={() => setShowExportModal(false)} />}
+
+      {showImportModal && (
+        <ImportSettingsModal
+          onClose={() => setShowImportModal(false)}
+          onImported={(settings) => setAppSettings(settings)}
+        />
+      )}
+
      {showInstructionsModal && (
        <ClaudeInstructionsModal
          instructions={globalInstructions}
@@ -28,6 +28,7 @@ import UrlToast, {
  URL_TOAST_SHORTCUT,
 } from "./UrlToast";
 import { trimSelection } from "./trimSelection";
+import { resolveTerminalGpuRendering } from "../../lib/terminalRenderer";
 import TerminalContextMenu from "./TerminalContextMenu";

 interface Props {
@@ -95,6 +96,7 @@ export default function TerminalView({ sessionId, active }: Props) {
  const webglRef = useRef<WebglAddon | null>(null);
  const detectorRef = useRef<UrlDetector | null>(null);
  const { sendInput, pasteImage, resize, onOutput, onExit } = useTerminal();
+  const gpuRenderingSetting = useAppState(s => s.appSettings?.terminal_gpu_rendering ?? null);
  const setTerminalHasSelection = useAppState(s => s.setTerminalHasSelection);
  const setTerminalAtBottom = useAppState(s => s.setTerminalAtBottom);
  const setScrollActiveToBottom = useAppState(s => s.setScrollActiveToBottom);
@@ -491,7 +493,11 @@ export default function TerminalView({ sessionId, active }: Props) {

    // Handle user input -> backend
    const inputDisposable = term.onData((data) => {
-      sendInput(sessionId, data);
+      // Ordered and coalesced by the queue in `useTerminal`; a rejection here
+      // means the session is gone, which the exit listener already reports.
+      sendInput(sessionId, data).catch((e) =>
+        console.error("Failed to send terminal input:", e)
+      );
    });

    // Detect user-initiated scroll-up (mouse wheel) to pause auto-follow.
@@ -684,7 +690,16 @@ export default function TerminalView({ sessionId, active }: Props) {
    const term = termRef.current;
    if (!term) return;

-    if (active) {
+    // Auto on macOS/Windows, off on Linux, overridable either way — see
+    // `resolveTerminalGpuRendering`. Loading the addon under a software-GL
+    // WebKitGTK is slower than xterm's canvas renderer, not faster.
+    const useGpu = resolveTerminalGpuRendering(gpuRenderingSetting, navigator.userAgent);
+
+    // The renderer and the activation work are independent: a terminal with
+    // GPU rendering switched off still has to fit and take focus when its tab
+    // becomes active. Keeping these in one branch made "GPU off" silently mean
+    // "never re-fit, never focus".
+    if (active && useGpu) {
      // Attach WebGL renderer
      if (!webglRef.current) {
        try {
@@ -699,19 +714,21 @@ export default function TerminalView({ sessionId, active }: Props) {
          // WebGL not available, canvas renderer is fine
        }
      }
+    } else if (webglRef.current) {
+      // Release the context — for inactive terminals, and when the setting
+      // turns GPU rendering off while this terminal is on screen.
+      try { webglRef.current.dispose(); } catch { /* ignore */ }
+      webglRef.current = null;
+    }
+
+    if (active) {
      fitRef.current?.fit();
      if (autoFollowRef.current) {
        term.scrollToBottom();
      }
      term.focus();
-    } else {
-      // Release WebGL context for inactive terminals
-      if (webglRef.current) {
-        try { webglRef.current.dispose(); } catch { /* ignore */ }
-        webglRef.current = null;
-      }
    }
-  }, [active]);
+  }, [active, gpuRenderingSetting]);

  // Auto-dismiss toast after 30 seconds — unless the user is standing in it.
  // A keyboard user who has just jumped into the toast is mid-decision, and
@@ -0,0 +1,77 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { render, screen, fireEvent } from "@testing-library/react";
+import Button from "./Button";
+
+const onClick = vi.fn();
+const onKeyDown = vi.fn();
+
+describe("Button", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it("still supports the native disabled attribute", () => {
+    render(
+      <Button disabled onClick={onClick}>
+        Save
+      </Button>,
+    );
+    expect(screen.getByRole("button", { name: "Save" })).toBeDisabled();
+  });
+
+  it("stays in the accessibility tree when unavailable, and says why", () => {
+    render(
+      <Button unavailable unavailableReason="Stop the container first.">
+        Save
+      </Button>,
+    );
+    const button = screen.getByRole("button", { name: "Save" });
+    expect(button).not.toBeDisabled();
+    expect(button).toHaveAttribute("aria-disabled", "true");
+    expect(button).toHaveAccessibleDescription("Stop the container first.");
+    // The reason is a description, not part of the name.
+    expect(button).toHaveAccessibleName("Save");
+  });
+
+  it("guards clicks and Enter/Space while unavailable", () => {
+    render(
+      <Button unavailable unavailableReason="Stop the container first." onClick={onClick}>
+        Save
+      </Button>,
+    );
+    const button = screen.getByRole("button", { name: "Save" });
+    fireEvent.click(button);
+    fireEvent.keyDown(button, { key: "Enter" });
+    fireEvent.keyDown(button, { key: " " });
+    expect(onClick).not.toHaveBeenCalled();
+  });
+
+  it("still forwards keys that are not activation keys", () => {
+    render(
+      <Button
+        unavailable
+        unavailableReason="Stop the container first."
+        onKeyDown={onKeyDown}
+      >
+        Save
+      </Button>,
+    );
+    fireEvent.keyDown(screen.getByRole("button", { name: "Save" }), {
+      key: "Escape",
+    });
+    expect(onKeyDown).toHaveBeenCalled();
+  });
+
+  it("behaves like an ordinary button when available", () => {
+    render(
+      <Button unavailable={false} unavailableReason="Stop the container first." onClick={onClick}>
+        Save
+      </Button>,
+    );
+    const button = screen.getByRole("button", { name: "Save" });
+    expect(button).not.toHaveAttribute("aria-disabled");
+    expect(button).toHaveAccessibleDescription("");
+    fireEvent.click(button);
+    expect(onClick).toHaveBeenCalledTimes(1);
+  });
+});
@@ -1,4 +1,5 @@
 import type { ButtonHTMLAttributes, ReactNode } from "react";
+import { useUnavailable } from "./unavailable";

 export type ButtonVariant = "primary" | "secondary" | "danger" | "ghost";
 export type ButtonSize = "sm" | "md";
@@ -7,22 +8,37 @@ interface Props extends ButtonHTMLAttributes<HTMLButtonElement> {
  variant?: ButtonVariant;
  size?: ButtonSize;
  children: ReactNode;
+  /**
+   * Unavailable, but still announced. Renders `aria-disabled` and wires
+   * `unavailableReason` to `aria-describedby` instead of using the native
+   * `disabled` attribute, which would take the button out of the tab order and
+   * out of the accessibility tree — reason and all. Clicks and Enter/Space are
+   * guarded for you. Prefer this over `disabled` whenever there is a reason
+   * worth telling the user.
+   */
+  unavailable?: boolean;
+  /** Why the button cannot be used. Required for `unavailable` to say anything. */
+  unavailableReason?: string;
 }

 /**
 * Real buttons with visible bounds and a ≥24px hit target.
 * Filled variants use the *-emphasis tokens so white text clears WCAG AA;
 * `--accent` stays reserved for foreground/link use.
+ *
+ * The `aria-disabled:` class mirrors below exist because Tailwind's
+ * `disabled:` variant only matches the native attribute, which `unavailable`
+ * deliberately does not set. Keep the two lists in step.
 */
 const VARIANTS: Record<ButtonVariant, string> = {
  primary:
-    "bg-[var(--accent-emphasis)] text-white border border-transparent hover:bg-[var(--accent-emphasis-hover)] disabled:bg-[var(--bg-tertiary)] disabled:text-[var(--text-disabled)] disabled:border-[var(--border-color)]",
+    "bg-[var(--accent-emphasis)] text-white border border-transparent hover:bg-[var(--accent-emphasis-hover)] disabled:bg-[var(--bg-tertiary)] disabled:text-[var(--text-disabled)] disabled:border-[var(--border-color)] aria-disabled:bg-[var(--bg-tertiary)] aria-disabled:text-[var(--text-disabled)] aria-disabled:border-[var(--border-color)] aria-disabled:hover:bg-[var(--bg-tertiary)]",
  secondary:
-    "bg-[var(--bg-tertiary)] text-[var(--text-primary)] border border-[var(--border-color)] hover:bg-[var(--border-color)] disabled:text-[var(--text-disabled)] disabled:hover:bg-[var(--bg-tertiary)]",
+    "bg-[var(--bg-tertiary)] text-[var(--text-primary)] border border-[var(--border-color)] hover:bg-[var(--border-color)] disabled:text-[var(--text-disabled)] disabled:hover:bg-[var(--bg-tertiary)] aria-disabled:text-[var(--text-disabled)] aria-disabled:hover:bg-[var(--bg-tertiary)]",
  danger:
-    "bg-transparent text-[var(--error)] border border-[var(--error)]/40 hover:bg-[var(--error-muted)] disabled:text-[var(--text-disabled)] disabled:border-[var(--border-color)] disabled:hover:bg-transparent",
+    "bg-transparent text-[var(--error)] border border-[var(--error)]/40 hover:bg-[var(--error-muted)] disabled:text-[var(--text-disabled)] disabled:border-[var(--border-color)] disabled:hover:bg-transparent aria-disabled:text-[var(--text-disabled)] aria-disabled:border-[var(--border-color)] aria-disabled:hover:bg-transparent",
  ghost:
-    "bg-transparent text-[var(--text-secondary)] border border-transparent hover:text-[var(--text-primary)] hover:bg-[var(--bg-tertiary)] disabled:text-[var(--text-disabled)] disabled:hover:bg-transparent",
+    "bg-transparent text-[var(--text-secondary)] border border-transparent hover:text-[var(--text-primary)] hover:bg-[var(--bg-tertiary)] disabled:text-[var(--text-disabled)] disabled:hover:bg-transparent aria-disabled:text-[var(--text-disabled)] aria-disabled:hover:text-[var(--text-disabled)] aria-disabled:hover:bg-transparent",
 };

 const SIZES: Record<ButtonSize, string> = {
@@ -35,16 +51,30 @@ export default function Button({
  size = "sm",
  className = "",
  type = "button",
+  unavailable = false,
+  unavailableReason = "",
  children,
  ...rest
 }: Props) {
+  const { controlProps, reasonNode } = useUnavailable({
+    unavailable,
+    reason: unavailableReason,
+    onClick: rest.onClick,
+    onKeyDown: rest.onKeyDown,
+  });
+
  return (
-    <button
-      type={type}
-      {...rest}
-      className={`inline-flex items-center justify-center whitespace-nowrap rounded-[var(--radius-control)] font-medium transition-colors disabled:cursor-not-allowed ${SIZES[size]} ${VARIANTS[variant]} ${className}`}
-    >
-      {children}
-    </button>
+    <>
+      <button
+        type={type}
+        {...rest}
+        {...controlProps}
+        className={`inline-flex items-center justify-center whitespace-nowrap rounded-[var(--radius-control)] font-medium transition-colors disabled:cursor-not-allowed aria-disabled:cursor-not-allowed ${SIZES[size]} ${VARIANTS[variant]} ${className}`}
+      >
+        {children}
+      </button>
+      {/* Outside the button: inside, the reason would join its accessible name. */}
+      {reasonNode}
+    </>
  );
 }
@@ -0,0 +1,87 @@
+import {
+  useId,
+  type KeyboardEventHandler,
+  type MouseEventHandler,
+  type ReactNode,
+} from "react";
+
+/** Keys a native `<button>` turns into a click. */
+const ACTIVATION_KEYS = new Set([" ", "Spacebar", "Enter"]);
+
+export interface UnavailableControlProps {
+  "aria-disabled"?: true;
+  "aria-describedby"?: string;
+  onClick?: MouseEventHandler<HTMLButtonElement>;
+  onKeyDown?: KeyboardEventHandler<HTMLButtonElement>;
+}
+
+export interface UnavailableControl {
+  /** Spread onto the control. Carries the guarded handlers. */
+  controlProps: UnavailableControlProps;
+  /**
+   * Render as a *sibling* of the control — inside it the reason would be
+   * appended to the accessible name instead of the description.
+   */
+  reasonNode: ReactNode;
+}
+
+/**
+ * Makes a control unavailable without hiding it from assistive technology.
+ *
+ * `disabled` takes an element out of the tab order *and* out of the
+ * accessibility tree, so the `title` explaining why it cannot be used is
+ * announced to nobody and shown only to a sighted user with a mouse. That is
+ * backwards: the people who most need the reason are the ones who never get
+ * it. `aria-disabled` keeps the control focusable and announced, and
+ * `aria-describedby` hands over the reason.
+ *
+ * The catch is that `aria-disabled` is advisory — it does not block clicks or
+ * Enter/Space the way `disabled` does. This hook therefore returns the guards
+ * along with the attributes, so a call site cannot take the announcement
+ * without the guard. Handlers that a form can reach without going through the
+ * control (Enter inside a text field submits the form) still have to guard
+ * themselves.
+ */
+export function useUnavailable({
+  unavailable,
+  reason,
+  onClick,
+  onKeyDown,
+}: {
+  unavailable: boolean;
+  reason: string;
+  onClick?: MouseEventHandler<HTMLButtonElement>;
+  onKeyDown?: KeyboardEventHandler<HTMLButtonElement>;
+}): UnavailableControl {
+  const reasonId = `${useId()}unavailable`;
+
+  if (!unavailable) {
+    return { controlProps: { onClick, onKeyDown }, reasonNode: null };
+  }
+
+  return {
+    controlProps: {
+      "aria-disabled": true,
+      "aria-describedby": reasonId,
+      onClick: (e) => {
+        e.preventDefault();
+        e.stopPropagation();
+      },
+      onKeyDown: (e) => {
+        if (!ACTIVATION_KEYS.has(e.key)) {
+          onKeyDown?.(e);
+          return;
+        }
+        // Suppress the default action before it can become a click, submit a
+        // form, or scroll the page.
+        e.preventDefault();
+        e.stopPropagation();
+      },
+    },
+    reasonNode: (
+      <span id={reasonId} className="sr-only">
+        {reason}
+      </span>
+    ),
+  };
+}
@@ -36,5 +36,9 @@ export function useSettings() {
    appSettings,
    loadSettings,
    saveSettings,
+    /** For a command that already returns the new `AppSettings` itself
+     *  (settings import) — updates the store without a redundant
+     *  `updateSettings` round trip through the backend. */
+    setAppSettings,
  };
 }
@@ -0,0 +1,83 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+
+// The queue lives at module scope in useTerminal, so the command layer is
+// mocked and the hook's `sendInput` is exercised through `renderHook`.
+const terminalInput = vi.fn<(sessionId: string, data: number[]) => Promise<void>>();
+
+vi.mock("../lib/tauri-commands", () => ({
+  terminalInput: (sessionId: string, data: number[]) => terminalInput(sessionId, data),
+  openTerminalSession: vi.fn(),
+  closeTerminalSession: vi.fn(),
+  terminalResize: vi.fn(),
+  pasteImageToTerminal: vi.fn(),
+  updateProject: vi.fn(),
+}));
+
+vi.mock("@tauri-apps/api/event", () => ({ listen: vi.fn() }));
+
+import { renderHook } from "@testing-library/react";
+import { useTerminal } from "./useTerminal";
+
+const decode = (bytes: number[]) => new TextDecoder().decode(new Uint8Array(bytes));
+
+describe("useTerminal input ordering", () => {
+  beforeEach(() => {
+    terminalInput.mockReset();
+  });
+
+  it("preserves order even when the underlying invokes resolve out of order", async () => {
+    // Make the *first* call the slowest, which is exactly the race that put a
+    // backspace behind the characters typed after it.
+    const resolvers: Array<() => void> = [];
+    terminalInput.mockImplementation(
+      () => new Promise<void>((resolve) => resolvers.push(resolve)),
+    );
+
+    const { result } = renderHook(() => useTerminal());
+
+    const first = result.current.sendInput("s1", "\x7f"); // backspace
+    const rest = ["a", "b", "c"].map((ch) => result.current.sendInput("s1", ch));
+
+    // Only one write may be in flight at a time.
+    expect(terminalInput).toHaveBeenCalledTimes(1);
+    expect(decode(terminalInput.mock.calls[0][1])).toBe("\x7f");
+
+    resolvers.shift()!();
+    await first;
+
+    // The three queued keystrokes coalesce into one ordered write.
+    expect(terminalInput).toHaveBeenCalledTimes(2);
+    expect(decode(terminalInput.mock.calls[1][1])).toBe("abc");
+
+    resolvers.shift()!();
+    await Promise.all(rest);
+
+    const sent = terminalInput.mock.calls.map((c) => decode(c[1])).join("");
+    expect(sent).toBe("\x7fabc");
+  });
+
+  it("settles each caller's promise and does not drop later writes on failure", async () => {
+    terminalInput.mockRejectedValueOnce(new Error("boom")).mockResolvedValue(undefined);
+
+    const { result } = renderHook(() => useTerminal());
+
+    await expect(result.current.sendInput("s2", "x")).rejects.toThrow("boom");
+    await expect(result.current.sendInput("s2", "y")).resolves.toBeUndefined();
+
+    expect(decode(terminalInput.mock.calls[1][1])).toBe("y");
+  });
+
+  it("keeps separate sessions independent", async () => {
+    terminalInput.mockResolvedValue(undefined);
+    const { result } = renderHook(() => useTerminal());
+
+    await Promise.all([
+      result.current.sendInput("a", "1"),
+      result.current.sendInput("b", "2"),
+    ]);
+
+    const bySession = terminalInput.mock.calls.map((c) => [c[0], decode(c[1])]);
+    expect(bySession).toContainEqual(["a", "1"]);
+    expect(bySession).toContainEqual(["b", "2"]);
+  });
+});
@@ -4,6 +4,86 @@ import { listen } from "@tauri-apps/api/event";
 import { useAppState } from "../store/appState";
 import * as commands from "../lib/tauri-commands";

+/**
+ * Per-session ordered write queue.
+ *
+ * Every keystroke used to be its own `invoke("terminal_input")`, and because
+ * that command is `async` on the Rust side Tauri spawns each one as an
+ * independent task. Those tasks then race for the session mutex in
+ * `ExecSessionManager::send_input`, so nothing preserved the order the bytes
+ * were typed in — the visible symptom was a backspace landing *after* the
+ * characters typed behind it. The serial writer task downstream cannot help,
+ * because the order is already lost by the time anything reaches the channel.
+ *
+ * The queue restores ordering the same way the web terminal gets it for free:
+ * one write in flight at a time, the next only after the previous resolves.
+ * Anything typed while a write is in flight coalesces into the next chunk,
+ * which also collapses a burst of typing into a couple of IPC round trips
+ * rather than one per key. Concatenating the byte arrays is safe — a PTY
+ * cannot tell one write of "ab" from writes of "a" then "b" — and each
+ * caller's promise still settles only when its own bytes have gone, so
+ * `await sendInput(...)` keeps the meaning it had.
+ *
+ * Module scope, not hook scope, because `useTerminal()` is called from several
+ * components (App for speech-to-text, TerminalView for typing and image paste,
+ * useProjectActions for tile commands). A per-hook queue would give each caller
+ * its own ordering and leave them racing against each other.
+ */
+type PendingWrite = {
+  bytes: number[];
+  resolve: () => void;
+  reject: (reason: unknown) => void;
+};
+
+const inputQueues = new Map<string, { pending: PendingWrite[]; draining: boolean }>();
+
+async function drainInputQueue(sessionId: string): Promise<void> {
+  const q = inputQueues.get(sessionId);
+  if (!q || q.draining) return;
+
+  q.draining = true;
+  try {
+    while (q.pending.length > 0) {
+      // Take everything queued so far as one batch, preserving order.
+      const batch = q.pending.splice(0, q.pending.length);
+      const bytes = batch.flatMap((w) => w.bytes);
+      try {
+        await commands.terminalInput(sessionId, bytes);
+        batch.forEach((w) => w.resolve());
+      } catch (err) {
+        // Reject only the writes in this batch. Anything queued while it was
+        // in flight is still pending and gets its own attempt on the next lap.
+        batch.forEach((w) => w.reject(err));
+      }
+    }
+  } finally {
+    q.draining = false;
+    // Drop the entry once idle so closed sessions do not accumulate.
+    if (q.pending.length === 0) inputQueues.delete(sessionId);
+  }
+}
+
+function enqueueInput(sessionId: string, bytes: number[]): Promise<void> {
+  return new Promise<void>((resolve, reject) => {
+    let q = inputQueues.get(sessionId);
+    if (!q) {
+      q = { pending: [], draining: false };
+      inputQueues.set(sessionId, q);
+    }
+    q.pending.push({ bytes, resolve, reject });
+    void drainInputQueue(sessionId);
+  });
+}
+
+/** Drop any queued input for a session that is going away. */
+function discardInputQueue(sessionId: string): void {
+  const q = inputQueues.get(sessionId);
+  if (!q) return;
+  const dropped = q.pending.splice(0, q.pending.length);
+  dropped.forEach((w) => w.reject(new Error(`Session ${sessionId} closed`)));
+  if (!q.draining) inputQueues.delete(sessionId);
+}
+
 export function useTerminal() {
  const { sessions, activeSessionId, addSession, removeSession, setActiveSession } =
    useAppState(
@@ -33,6 +113,7 @@ export function useTerminal() {
      const session = currentSessions.find((s) => s.id === sessionId);
      const project = session ? projects.find((p) => p.id === session.projectId) : undefined;

+      discardInputQueue(sessionId);
      await commands.closeTerminalSession(sessionId);
      removeSession(sessionId);

@@ -54,7 +135,7 @@ export function useTerminal() {
  const sendInput = useCallback(
    async (sessionId: string, data: string) => {
      const bytes = Array.from(new TextEncoder().encode(data));
-      await commands.terminalInput(sessionId, bytes);
+      await enqueueInput(sessionId, bytes);
    },
    [],
  );
@@ -0,0 +1,125 @@
+import { describe, it, expect } from "vitest";
+import { describeImport, describeImportWarnings } from "./settingsImportPreview";
+import type { SettingsImportPreview } from "./types";
+
+function preview(overrides: Partial<SettingsImportPreview> = {}): SettingsImportPreview {
+  return {
+    exported_at: "2026-08-27T00:00:00Z",
+    app_version: "0.4.14",
+    custom_env_var_count: 0,
+    gateway_model_count: 0,
+    has_claude_code_settings: false,
+    has_claude_oauth_token: false,
+    has_gateway_api_key: false,
+    has_gateway_master_key: false,
+    has_web_terminal_access_token: false,
+    enables_web_terminal: false,
+    ollama_base_url: null,
+    llamacpp_base_url: null,
+    openai_compatible_base_url: null,
+    gateway_api_base: null,
+    image_source: "registry",
+    custom_image_name: null,
+    ...overrides,
+  };
+}
+
+describe("describeImport", () => {
+  it("always names the settings replacement, even with nothing else set", () => {
+    expect(describeImport(preview())).toEqual([
+      "Your global settings (all of them — this replaces what's here now)",
+    ]);
+  });
+
+  it("singularizes a count of exactly one", () => {
+    const items = describeImport(preview({ custom_env_var_count: 1, gateway_model_count: 1 }));
+    expect(items).toContain("1 global custom env var");
+    expect(items).toContain("1 gateway model");
+  });
+
+  it("pluralizes counts greater than one", () => {
+    const items = describeImport(preview({ custom_env_var_count: 3, gateway_model_count: 2 }));
+    expect(items).toContain("3 global custom env vars");
+    expect(items).toContain("2 gateway models");
+  });
+
+  it("names every present secret and setting without naming absent ones", () => {
+    const items = describeImport(
+      preview({
+        has_claude_code_settings: true,
+        has_claude_oauth_token: true,
+        has_gateway_api_key: true,
+        has_gateway_master_key: true,
+      }),
+    );
+    expect(items).toContain("Global Claude Code settings");
+    expect(items).toContain("Your shared Claude login");
+    expect(items).toContain("The gateway provider API key");
+    expect(items).toContain("The gateway master key");
+    // None of the count-based items, since both counts are 0.
+    expect(items.some((i) => i.includes("env var"))).toBe(false);
+    expect(items.some((i) => i.includes("gateway model"))).toBe(false);
+  });
+
+  it("names the web terminal access token like any other present secret", () => {
+    const items = describeImport(preview({ has_web_terminal_access_token: true }));
+    expect(items).toContain("The web terminal access token");
+  });
+
+  it("names custom base URLs verbatim, since they're endpoints rather than secrets", () => {
+    const items = describeImport(
+      preview({
+        ollama_base_url: "http://10.0.0.5:11434",
+        gateway_api_base: "https://gateway.example/v1",
+      }),
+    );
+    expect(items).toContain("Ollama server: http://10.0.0.5:11434");
+    expect(items).toContain("Gateway upstream: https://gateway.example/v1");
+    expect(items.some((i) => i.includes("llama.cpp"))).toBe(false);
+    expect(items.some((i) => i.includes("OpenAI-compatible"))).toBe(false);
+  });
+
+  it("names a custom Docker image when set, falling back to a placeholder if unnamed", () => {
+    expect(
+      describeImport(preview({ image_source: "custom", custom_image_name: "ghcr.io/me/triple-c" })),
+    ).toContain("Docker image: ghcr.io/me/triple-c");
+    expect(describeImport(preview({ image_source: "custom", custom_image_name: null }))).toContain(
+      "Docker image: (no image name set)",
+    );
+    expect(describeImport(preview({ image_source: "registry" })).some((i) => i.includes("Docker image"))).toBe(
+      false,
+    );
+  });
+});
+
+describe("describeImportWarnings", () => {
+  it("is empty when nothing about the import needs extra attention", () => {
+    expect(describeImportWarnings(preview())).toEqual([]);
+  });
+
+  it("warns when the import enables the web terminal, regardless of the token", () => {
+    // `enabled` and the token are independent — the warning is about the
+    // service turning on, whether or not a token came with it.
+    expect(describeImportWarnings(preview({ enables_web_terminal: true }))).toEqual([
+      "Enables the remote web terminal, which listens on your network.",
+    ]);
+    expect(
+      describeImportWarnings(
+        preview({ enables_web_terminal: true, has_web_terminal_access_token: true }),
+      ),
+    ).toHaveLength(1);
+  });
+
+  it("warns about a dormant web terminal token even while the terminal stays off", () => {
+    expect(describeImportWarnings(preview({ has_web_terminal_access_token: true }))).toEqual([
+      "Includes a web terminal access token that will activate the next time the web terminal is turned on.",
+    ]);
+  });
+
+  it("warns about a custom Docker image every time, not only when it changes", () => {
+    expect(
+      describeImportWarnings(preview({ image_source: "custom", custom_image_name: "evil:latest" })),
+    ).toEqual(["Runs every project container from a custom Docker image: evil:latest."]);
+    expect(describeImportWarnings(preview({ image_source: "registry" }))).toEqual([]);
+  });
+});
@@ -0,0 +1,67 @@
+import type { SettingsImportPreview } from "./types";
+
+/** Named things a `SettingsImportPreview` says an import will change, for
+ *  `ImportSettingsModal`'s confirmation list. Does not include anything
+ *  `describeImportWarnings` covers — those get their own, more visible
+ *  treatment rather than blending into this list. */
+export function describeImport(preview: SettingsImportPreview): string[] {
+  const items: string[] = ["Your global settings (all of them — this replaces what's here now)"];
+  if (preview.custom_env_var_count > 0) {
+    items.push(
+      `${preview.custom_env_var_count} global custom env var${preview.custom_env_var_count === 1 ? "" : "s"}`,
+    );
+  }
+  if (preview.has_claude_code_settings) items.push("Global Claude Code settings");
+  if (preview.gateway_model_count > 0) {
+    items.push(`${preview.gateway_model_count} gateway model${preview.gateway_model_count === 1 ? "" : "s"}`);
+  }
+  if (preview.has_claude_oauth_token) items.push("Your shared Claude login");
+  if (preview.has_gateway_api_key) items.push("The gateway provider API key");
+  if (preview.has_gateway_master_key) items.push("The gateway master key");
+  if (preview.has_web_terminal_access_token) items.push("The web terminal access token");
+  if (preview.ollama_base_url) items.push(`Ollama server: ${preview.ollama_base_url}`);
+  if (preview.llamacpp_base_url) items.push(`llama.cpp server: ${preview.llamacpp_base_url}`);
+  if (preview.openai_compatible_base_url) {
+    items.push(`OpenAI-compatible server: ${preview.openai_compatible_base_url}`);
+  }
+  if (preview.gateway_api_base) items.push(`Gateway upstream: ${preview.gateway_api_base}`);
+  if (preview.image_source === "custom") {
+    items.push(`Docker image: ${preview.custom_image_name ?? "(no image name set)"}`);
+  }
+  return items;
+}
+
+/**
+ * Things about an import that deserve more attention than a bullet in a
+ * long list — deliberately its own function rather than a flag inside
+ * `describeImport`: a setting that turns on a network-listening service is
+ * exactly the kind of change a "your settings were replaced" summary is bad
+ * at surfacing, on purpose or (if the file came from someone else) not.
+ *
+ * A token that arrives with the terminal left *off* gets its own warning
+ * too, distinct from the "enables it now" one: `start_web_terminal` only
+ * mints a fresh token when none is already set, so a planted token here
+ * would silently become live the next time someone flips the terminal on
+ * through the UI, with no import-time signal that it wasn't freshly
+ * generated.
+ *
+ * A custom Docker image gets a warning every time, not just on change: it's
+ * the image every project container is created from, so it's worth calling
+ * out regardless of what was configured before the import.
+ */
+export function describeImportWarnings(preview: SettingsImportPreview): string[] {
+  const warnings: string[] = [];
+  if (preview.enables_web_terminal) {
+    warnings.push("Enables the remote web terminal, which listens on your network.");
+  } else if (preview.has_web_terminal_access_token) {
+    warnings.push(
+      "Includes a web terminal access token that will activate the next time the web terminal is turned on.",
+    );
+  }
+  if (preview.image_source === "custom") {
+    warnings.push(
+      `Runs every project container from a custom Docker image: ${preview.custom_image_name ?? "(no image name set)"}.`,
+    );
+  }
+  return warnings;
+}
@@ -1,5 +1,5 @@
 import { invoke } from "@tauri-apps/api/core";
-import type { Project, ProjectPath, ProjectRemovalReport, ProjectResetOutcome, ContainerInfo, AppSettings, UpdateInfo, ImageUpdateInfo, FileEntry, FileContents, WebTerminalInfo, SttStatus, GatewayStatus, InstallOptions, ClaudeSession, ContainerCapabilities, ScheduledTask, ScheduledTaskInput, SchedulerNotification, AuthBridgeStatus, BrowserViewStatus, BrowserViewPopoutState, BrowserPageState, PlaywrightDetection, BrowserSetupOutcome, BrowserInstallTarget, ContainerStaleness, MigrationOptions, MigrationReport, MigrationState, ClearTokenOutcome, CaCertInfo, UploadOutcome } from "./types";
+import type { Project, ProjectPath, ProjectRemovalReport, ProjectResetOutcome, ContainerInfo, AppSettings, SettingsImportPreview, SettingsImportOutcome, UpdateInfo, ImageUpdateInfo, FileEntry, FileContents, WebTerminalInfo, SttStatus, GatewayStatus, InstallOptions, ClaudeSession, ContainerCapabilities, ScheduledTask, ScheduledTaskInput, SchedulerNotification, AuthBridgeStatus, BrowserViewStatus, BrowserViewPopoutState, BrowserPageState, PlaywrightDetection, BrowserSetupOutcome, BrowserInstallTarget, ContainerStaleness, MigrationOptions, MigrationReport, MigrationState, ClearTokenOutcome, CaCertInfo, UploadOutcome } from "./types";

 // Docker
 export const checkDocker = () => invoke<boolean>("check_docker");
@@ -42,6 +42,15 @@ export const inspectCaCertPath = (path: string) =>
 export const detectHostTimezone = () =>
  invoke<string>("detect_host_timezone");

+// Settings export/import — `false`/`null` mean the save/open dialog was
+// dismissed, not an error.
+export const exportSettings = (password: string) =>
+  invoke<boolean>("export_settings", { password });
+export const previewSettingsImport = (password: string) =>
+  invoke<SettingsImportPreview | null>("preview_settings_import", { password });
+export const applySettingsImport = (password: string) =>
+  invoke<SettingsImportOutcome>("apply_settings_import", { password });
+
 // AWS
 export const awsSsoRefresh = (projectId: string) =>
  invoke<void>("aws_sso_refresh", { projectId });
@@ -0,0 +1,39 @@
+import { describe, it, expect } from "vitest";
+import { isLinuxWebview, resolveTerminalGpuRendering } from "./terminalRenderer";
+
+const LINUX = "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/605.1.15 Safari/605.1.15";
+const MAC = "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/605.1.15 Safari/605.1.15";
+const WINDOWS = "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 Chrome/120 Safari/537.36";
+const ANDROID = "Mozilla/5.0 (Linux; Android 14) AppleWebKit/537.36 Chrome/120 Mobile Safari/537.36";
+
+describe("isLinuxWebview", () => {
+  it("recognises desktop Linux", () => {
+    expect(isLinuxWebview(LINUX)).toBe(true);
+  });
+
+  it("does not count Android as desktop Linux", () => {
+    expect(isLinuxWebview(ANDROID)).toBe(false);
+  });
+
+  it("rejects the other desktop platforms", () => {
+    expect(isLinuxWebview(MAC)).toBe(false);
+    expect(isLinuxWebview(WINDOWS)).toBe(false);
+  });
+});
+
+describe("resolveTerminalGpuRendering", () => {
+  it("auto is off on Linux, where WebGL falls back to software rendering", () => {
+    expect(resolveTerminalGpuRendering(null, LINUX)).toBe(false);
+    expect(resolveTerminalGpuRendering(undefined, LINUX)).toBe(false);
+  });
+
+  it("auto is on elsewhere", () => {
+    expect(resolveTerminalGpuRendering(null, MAC)).toBe(true);
+    expect(resolveTerminalGpuRendering(null, WINDOWS)).toBe(true);
+  });
+
+  it("an explicit setting wins on every platform", () => {
+    expect(resolveTerminalGpuRendering(true, LINUX)).toBe(true);
+    expect(resolveTerminalGpuRendering(false, MAC)).toBe(false);
+  });
+});
@@ -0,0 +1,28 @@
+/**
+ * Decides whether the terminal loads `@xterm/addon-webgl`.
+ *
+ * Split out of `TerminalView` so it can be unit-tested without standing up a
+ * terminal, and so the platform rule lives in exactly one place.
+ */
+
+/** True when the webview is running on Linux (WebKitGTK), excluding Android. */
+export function isLinuxWebview(userAgent: string): boolean {
+  return /\bLinux\b/.test(userAgent) && !/\bAndroid\b/.test(userAgent);
+}
+
+/**
+ * Resolve the effective WebGL setting.
+ *
+ * `setting` is `AppSettings.terminal_gpu_rendering`: `true`/`false` force the
+ * answer, `null`/`undefined` mean auto. Auto is on everywhere except Linux —
+ * there the app disables WebKitGTK's DMA-BUF renderer at startup (triple-c#34),
+ * which leaves WebGL present but software-rasterised, so loading the addon is
+ * slower than the canvas renderer it would otherwise have fallen back to.
+ */
+export function resolveTerminalGpuRendering(
+  setting: boolean | null | undefined,
+  userAgent: string,
+): boolean {
+  if (typeof setting === "boolean") return setting;
+  return !isLinuxWebview(userAgent);
+}
@@ -290,6 +290,52 @@ export interface AppSettings {
  stt: SttSettings;
  gateway: GatewaySettings;
  global_claude_code_settings: ClaudeCodeSettings | null;
+  /** Whether the terminal loads the WebGL renderer. `null` is auto: on
+   *  everywhere except Linux, where the DMA-BUF workaround leaves WebGL
+   *  backed by software rasterisation and the addon ends up slower than the
+   *  canvas renderer it would otherwise fall back to. See
+   *  `resolveTerminalGpuRendering` in `lib/terminalRenderer.ts`. */
+  terminal_gpu_rendering: boolean | null;
+}
+
+/** What `preview_settings_import` returns before anything is applied —
+ *  counts and presence flags only, never a secret value itself. Built from
+ *  this, not from the raw import file, which the frontend never sees. */
+export interface SettingsImportPreview {
+  exported_at: string;
+  app_version: string;
+  custom_env_var_count: number;
+  gateway_model_count: number;
+  has_claude_code_settings: boolean;
+  has_claude_oauth_token: boolean;
+  has_gateway_api_key: boolean;
+  has_gateway_master_key: boolean;
+  has_web_terminal_access_token: boolean;
+  /** Whether the import turns the web terminal on — surfaced separately
+   *  from the token above since either can be true without the other, and
+   *  "this enables a service that listens on your network" must not hide
+   *  inside a generic "settings replaced" summary. */
+  enables_web_terminal: boolean;
+  /** Non-blank custom base URLs the import would set — endpoints, not
+   *  secrets, so shown verbatim to disclose a redirect of model traffic. */
+  ollama_base_url: string | null;
+  llamacpp_base_url: string | null;
+  openai_compatible_base_url: string | null;
+  gateway_api_base: string | null;
+  /** Whether the import sets a custom Docker image, and its name if so —
+   *  this is the image every project container is created from, so worth
+   *  more attention than an ordinary setting. */
+  image_source: ImageSource;
+  custom_image_name: string | null;
+}
+
+/** What `apply_settings_import` returns: the settings that were actually
+ *  saved, plus a note for each keychain secret the import carried but could
+ *  not be restored (a partial keychain failure must not read as unqualified
+ *  success just because the settings half went through). */
+export interface SettingsImportOutcome {
+  settings: AppSettings;
+  secret_restore_warnings: string[];
 }

 /** What `inspect_ca_cert_path` reports about a corporate CA path. Errors ride
@@ -1,86 +0,0 @@
-# Maintainer: Triple-C Contributors
-#
-# This file is regenerated by .gitea/workflows/publish-aur-package.yml on every
-# publish — pkgver, the source URL and sha256sums are rewritten from the real,
-# already-uploaded release asset, never guessed. Editing pkgver/source/
-# sha256sums by hand here only matters until the next automated run overwrites
-# them; everything else (depends, pkgdesc, package()) is meant to be hand-
-# maintained normally.
-#
-# "-bin" rather than building from source: this repackages the same .deb
-# build-app.yml already produces and publishes, so a user gets exactly the
-# binary the project ships and tests, and `makepkg` never needs a Rust
-# toolchain, Node, or the dozen -dev packages CLAUDE.md lists for building
-# Triple-C itself. The trade-off is the one every "-bin" package makes: it
-# assumes the glibc the CI runner (Ubuntu 24.04) linked against is compatible
-# with the installing system's — true for essentially every currently
-# supported Arch install, since Arch tracks glibc newer than Ubuntu 24.04
-# ships, and forward compatibility is the direction that holds.
-pkgname=triple-c-bin
-pkgver=0.4.0
-pkgrel=1
-pkgdesc="Sandbox Claude Code inside Docker containers"
-arch=('x86_64')
-url="https://github.com/shadowdao/triple-c"
-license=('MIT')
-# Verified against a real release asset (v0.4.14), not Tauri's generic docs:
-# downloaded Triple-C_0.4.14_amd64.deb, installed each of these into a real
-# Arch container, and re-ran `ldd` on the actual binary until nothing came
-# back "not found". `pango` and `libayatana-appindicator` were both in an
-# earlier draft — pango isn't directly linked (gtk3 already pulls it in
-# transitively, and namcap correctly flags declaring it as redundant), and
-# libayatana-appindicator is in Tauri's own linux dependency list but this
-# binary never links it at all: there is no tray icon or menu in this app
-# (see CLAUDE.md's note that `core:menu`/`core:tray` are dropped for the
-# same reason), so it was never a real dependency to begin with.
-depends=('cairo' 'desktop-file-utils' 'gdk-pixbuf2' 'glib2' 'gtk3'
-         'hicolor-icon-theme' 'libsoup3' 'webkit2gtk-4.1')
-optdepends=('docker: to actually run the sandboxed containers'
-            'xdg-utils: opening links from the app in your default browser')
-provides=('triple-c')
-conflicts=('triple-c')
-# !strip: the upstream .deb's binary is already the release build Tauri
-# produced and tested; re-stripping a prebuilt binary is unnecessary risk for
-# no benefit. It's also what actually suppresses makepkg's debug-package
-# machinery here (debug-package extraction requires strip; verified in a
-# real build — with !strip alone, no debug package is produced at all).
-# !debug is kept anyway, explicit about intent rather than relying on that
-# side effect. Without either, makepkg built a usr/src/debug/triple-c-bin
-# tree containing a dangling .build-id symlink, which is a real namcap
-# error (not just the empty-directory warning it looks like) — there is no
-# debug info in this release binary for the machinery to have extracted in
-# the first place.
-options=('!strip' '!debug')
-# Tauri names the asset after `productName` verbatim ("Triple-C"), not the
-# lowercase Cargo binary name — verified against the real release, not
-# assumed; a lowercase guess here would 404. The LICENSE fetch is separate
-# because the .deb itself carries no license file — namcap flags an MIT
-# package with nothing under /usr/share/licenses/ as an error, correctly.
-source=("Triple-C_${pkgver}_amd64.deb::https://github.com/shadowdao/triple-c/releases/download/v${pkgver}/Triple-C_${pkgver}_amd64.deb"
-        "LICENSE::https://raw.githubusercontent.com/shadowdao/triple-c/v${pkgver}/LICENSE")
-sha256sums=('SKIP'
-            'SKIP')
-
-package() {
-  cd "$srcdir"
-  # A .deb is an ar archive of debian-binary, control.tar.*, data.tar.* — `ar`
-  # (part of base-devel's binutils) pulls just the payload out. Extracting
-  # that tar directly into $pkgdir works here with no path rewriting at all:
-  # verified against the real archive, whose entire payload is
-  # usr/bin/triple-c, usr/share/applications/Triple-C.desktop and
-  # usr/share/icons/hicolor/*/apps/triple-c.png — Tauri's Linux bundle for
-  # this app carries no separate resource directory under usr/lib/, so there
-  # is nothing that could disagree between Debian's and Arch's package trees
-  # for it to land in the wrong place.
-  #
-  # Globbed rather than named literally: the publish workflow discovers the
-  # real asset name from the release itself specifically so a Tauri bundler
-  # naming change can't silently break this — naming the file again here
-  # would throw that away and fail this one line with an opaque "No such
-  # file or directory" instead. `source=()` above guarantees exactly one
-  # `*_amd64.deb` entry, so the glob can only ever match that one file.
-  ar x ./*_amd64.deb
-  tar xf data.tar.* -C "$pkgdir"
-
-  install -Dm644 "$srcdir/LICENSE" "$pkgdir/usr/share/licenses/$pkgname/LICENSE"
-}
@@ -1,53 +0,0 @@
-# Arch / CachyOS package
-
-`PKGBUILD` here is the AUR `triple-c-bin` package's template — see triple-c#34
-(the "I would like to also have an Arch/CachyOS native version" part of it).
-
-## Why "-bin"
-
-It repackages the same `.deb` `build-app.yml` already produces, rather than
-building from source. That means `makepkg` never needs a Rust toolchain,
-Node, or the dozen `-dev` packages CLAUDE.md lists for building Triple-C
-itself — and a user gets exactly the binary the project ships and tests,
-built on Ubuntu 24.04 in CI. Verified end to end against a real release
-(v0.4.14): downloaded the actual `.deb`, confirmed every `depends` entry
-against a real `ldd` of the actual binary (two packages that looked right
-from Tauri's own docs — `pango`, `libayatana-appindicator` — turned out not
-to be real dependencies of *this* binary and were dropped), and ran a real
-`makepkg`/`namcap`/`pacman -U` cycle rather than guessing at the shape.
-
-## Publishing
-
-`.gitea/workflows/publish-aur-package.yml` does the actual work: given a
-version (or "latest" if none is given), it finds that release's real Linux
-asset on GitHub, downloads it, computes real checksums, renders this
-template into a version-specific PKGBUILD, validates it with `makepkg` and
-`namcap` inside a real Arch container, and pushes the result to AUR.
-
-It is `workflow_dispatch`-only, deliberately — see the workflow file's own
-header comment for why an automatic trigger isn't safe here (the same reason
-`sync-release.yml` didn't work and was removed in triple-c#32).
-
-**Before it can push anything**, an AUR account has to exist and the
-`triple-c-bin` package has to have been created (or you added as a
-co-maintainer) under it — both are one-time, manual steps on
-https://aur.archlinux.org, since there's no API to automate creating an
-account or a new package. Once that's done, add the account's SSH private
-key as the `AUR_SSH_PRIVATE_KEY` secret on this repo. Until that secret
-exists, the workflow fails at the "Push to AUR" step with a message saying
-so, rather than silently doing nothing.
-
-## What's hand-maintained vs. generated
-
-`pkgver`/`pkgrel`/`source`/`sha256sums` in this file are placeholders —
-the workflow rewrites them for every real publish and never commits the
-result back here, so don't read this file's `pkgver` as "the last published
-version." Everything else (`depends`, `pkgdesc`, `package()`) is meant to be
-edited by hand normally, the same as any other PKGBUILD.
-
-**A hand-edit made directly in the AUR repo is silently overwritten the
-next time this workflow runs.** Every run renders fresh from *this*
-repo's template rather than starting from whatever AUR's copy currently
-looks like, so a quick fix pushed straight to AUR (bumping `pkgrel` for a
-packaging-only issue, say) survives only until the next dispatch. Make
-the fix here instead.
@@ -0,0 +1,127 @@
+#!/bin/sh
+# Register a Triple-C AppImage with the desktop, so it appears in the app
+# launcher with its icon instead of only being runnable from a file manager.
+#
+# An AppImage is a single executable file and nothing more: it ships a
+# `.desktop` entry and icons *inside* itself, but nothing on the host ever
+# reads them, because nothing installed it. This script does what a package
+# manager's install hooks would — copies the icons into the user's icon theme
+# and writes a `.desktop` entry pointing at wherever the AppImage actually
+# lives.
+#
+#     ./scripts/install-appimage.sh ~/Apps/Triple-C_0.4.17_amd64.AppImage
+#     ./scripts/install-appimage.sh --uninstall
+#
+# Everything goes under ~/.local/share, so there is no sudo and no root-owned
+# file to clean up later. The AppImage itself is never copied or moved — the
+# launcher entry points at the path you give here, so keep the file somewhere
+# stable (`~/Apps` or `~/.local/bin`, not `~/Downloads`) or re-run this after
+# moving it.
+#
+# Extraction uses `--appimage-extract`, which unpacks the payload directly and
+# needs no FUSE. So this script works even on a system where *running* the
+# AppImage would need `fuse2` installed first.
+
+set -eu
+
+APP_ID="triple-c"
+DESKTOP_DIR="${XDG_DATA_HOME:-$HOME/.local/share}/applications"
+ICON_DIR="${XDG_DATA_HOME:-$HOME/.local/share}/icons/hicolor"
+DESKTOP_FILE="${DESKTOP_DIR}/${APP_ID}.desktop"
+
+refresh_caches() {
+    # Both are best-effort: a minimal desktop may ship neither, and neither
+    # failing means the install did not work.
+    if command -v update-desktop-database >/dev/null 2>&1; then
+        update-desktop-database "${DESKTOP_DIR}" 2>/dev/null || true
+    fi
+    if command -v gtk-update-icon-cache >/dev/null 2>&1; then
+        gtk-update-icon-cache -f -t "${ICON_DIR}" 2>/dev/null || true
+    fi
+}
+
+uninstall() {
+    rm -f "${DESKTOP_FILE}"
+    find "${ICON_DIR}" -name "${APP_ID}.png" -delete 2>/dev/null || true
+    refresh_caches
+    echo "Removed the Triple-C launcher entry and icons."
+    echo "The AppImage itself was not touched."
+}
+
+if [ "${1:-}" = "--uninstall" ]; then
+    uninstall
+    exit 0
+fi
+
+APPIMAGE="${1:-}"
+if [ -z "${APPIMAGE}" ]; then
+    echo "usage: $0 [--uninstall] /path/to/Triple-C_<version>_amd64.AppImage" >&2
+    exit 2
+fi
+if [ ! -f "${APPIMAGE}" ]; then
+    echo "No such file: ${APPIMAGE}" >&2
+    exit 1
+fi
+
+# An absolute path, because the .desktop Exec line is read from anywhere.
+APPIMAGE=$(cd "$(dirname "${APPIMAGE}")" && printf '%s/%s' "$(pwd)" "$(basename "${APPIMAGE}")")
+
+if [ ! -x "${APPIMAGE}" ]; then
+    echo "Making ${APPIMAGE} executable"
+    chmod +x "${APPIMAGE}"
+fi
+
+WORK=$(mktemp -d)
+# shellcheck disable=SC2064  # WORK is expanded now on purpose.
+trap "rm -rf '${WORK}'" EXIT INT TERM
+
+echo "Extracting bundled icons from $(basename "${APPIMAGE}")..."
+( cd "${WORK}" && "${APPIMAGE}" --appimage-extract >/dev/null )
+
+SRC="${WORK}/squashfs-root"
+if [ ! -d "${SRC}/usr/share/icons/hicolor" ]; then
+    echo "That AppImage has no bundled icons — is it really Triple-C?" >&2
+    exit 1
+fi
+
+# Copy every size the bundle ships, keeping the theme's directory layout.
+COUNT=0
+while IFS= read -r icon; do
+    [ -n "${icon}" ] || continue
+    rel=${icon#"${SRC}/usr/share/icons/hicolor/"}
+    install -Dm644 "${icon}" "${ICON_DIR}/${rel}"
+    COUNT=$((COUNT + 1))
+done <<EOF
+$(find "${SRC}/usr/share/icons/hicolor" -name "${APP_ID}.png")
+EOF
+echo "Installed ${COUNT} icon size(s) into ${ICON_DIR}"
+
+# Written rather than copied from the bundle. The bundled entry has
+# `Exec=triple-c`, which resolves only inside the running AppImage's own mount
+# — from the host it names a binary that is not on PATH, so the launcher entry
+# would appear and then fail to start anything. `Categories` is empty in the
+# bundle too, which leaves the entry to fall into "Other" in most menus.
+# `StartupWMClass` is kept exactly as the bundle sets it: it is what lets the
+# shell match the running window to this entry, so the taskbar shows the real
+# icon instead of a generic placeholder.
+mkdir -p "${DESKTOP_DIR}"
+cat > "${DESKTOP_FILE}" <<DESKTOP
+[Desktop Entry]
+Type=Application
+Name=Triple-C
+Comment=Run Claude Code sandboxed in Docker containers
+Exec=${APPIMAGE} %U
+Icon=${APP_ID}
+Terminal=false
+Categories=Development;
+StartupWMClass=${APP_ID}
+DESKTOP
+chmod 644 "${DESKTOP_FILE}"
+echo "Wrote ${DESKTOP_FILE}"
+
+refresh_caches
+
+echo
+echo "Done. Triple-C should now be in your app launcher."
+echo "If the icon is generic or the entry is missing, log out and back in —"
+echo "see \"App Icon Missing After Installing (Linux)\" in HOW-TO-USE.md."