Summary
In a Retool Cloud app, certain icon names (e.g. bold/interface-arrows-button-reload) have been retired from Retool's asset CDN, so their dynamically imported JS modules (retool-edge.com/assets_vjs/dynamic-*.js) return a 404 with no Access-Control-Allow-Origin header. This surfaces as a CORS failure, rejects during React render, and the error boundary remounts the affected subtree — making parts of the app appear to reload (notably on tab switches when previously hidden containers first mount).
AI Response
This behavior is a known, staff-acknowledged consequence of how Retool loads icons: each icon is fetched as a separate dynamically imported module, and a Retool team member has confirmed the root cause is a CORS issue tied specifically to that dynamic icon loading, which was documented internally. The most reliable fix available today is to swap any retired icon name for a currently-valid one from the built-in icon picker (or substitute an uploaded image), which stops the failing dynamic import and prevents the subtree from remounting. Because any app in the org that references a retired icon name has the same defect, it's worth auditing other apps for the same icon references and replacing them proactively.
Sources
Centralizing icon definitions
A Retool team member confirms the same root cause — icons load dynamically and the failure surfaces as a CORS issue, documented internally — directly corroborating the reported mechanism.
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