While investigating a separate timeout, I noticed that the "legacy" implementation of the webview_flutter_web package is accessing the iFrame element on the DOM before it's injected into the page:

• https://github.com/flutter/packages/blob/3379e51a042af5efe5c5e1e69e0f3ce5d979351f/packages/webview_flutter/webview_flutter_web/lib/src/webview_flutter_web_legacy.dart#L50-L51

That code fails consistently in flutter, and needs to be fixed. It's unclear to me how this went through CI, but it's also unclear to me how integration tests for this package ever do anything, since they seem to be using dart:io (???)

• https://github.com/flutter/packages/blob/3379e51a042af5efe5c5e1e69e0f3ce5d979351f/packages/webview_flutter/webview_flutter_web/example/integration_test/legacy/webview_flutter_test.dart#L7