shadowdao
849f432330
The canonical Craft.js state from real saves shows that layout shells (Section, BackgroundSection, HeroSimple, FeaturesGrid, ColumnLayout, CTASection, FormContainer, Navbar, Footer) all serialize with isCanvas:false. Only Container instances are canvases. The shells use internal <Element canvas id="..."> linkedNodes for their drop targets. Our previous CANVAS_TYPES set claimed all those shells were canvases, which made Craft.js's toNodeTree walker hit an uncaught Invariant — the shell asserted "I'm a canvas" but its render ignores data.nodes, so the walker would chase phantom children.
