Summary
With the new AI app builder, apps can't be embedded inside an iframe (something that worked with classic apps), which is blocking migration of a key app that needs to be embedded within Salesforce.
AI Response
This is a known, confirmed limitation: apps built in the new app builder cannot currently be embedded in an iframe. New app builder pages enforce a restrictive frame-src content security policy that blocks them from rendering inside an iframe, and the auth callback breaks in that context. Retool staff have confirmed this scenario is not yet supported but is being tracked internally as a high-priority request. For now, the only reliable path is to link out to the new app rather than iframe it, or to keep the app in the classic builder until native embed support ships.
Sources
Embedding new Retool AI app into Classic app
A Retool staff member confirms embedding a new app builder app via iframe (yielding an 'Invalid auth callback' error) isn't currently supported but is being tracked as a high-priority request.
Corroborates the same limitation and explains the root cause—the new app builder page enforces a restrictive frame-src CSP header—while confirming the recommended interim approach is to link out rather than iframe.
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