The Error balloon/toast overlay is broken in 14.2

[kamyarkaviani]

In nextjs 14.1, when an error is caught by an error boundary in error.tsx, in development mode, you get a toast/balloon in the corner of the page showing there is an error that when clicked, gives a nice stacktrace with a link to the line of code causing it.

This got killed in 14.2?? This is a create-next-app with nothing changed but adding an error.tsx and throwing a test error. In 14.2, the balloon never appears. Why? How can I have this back? Is it a bug, or is there now a setting I should provide to get this error overlay back, to show the error in dev mode?