Created attachment 424008 [details] CORS error on ResizeObserver loop 'ResizeObserver loop completed with undelivered notifications' error is causing the CORS error why? User sees only 'Script error. Error in cross-origin script..'. It looks like a default message when an error has no file, line, or column, which is usually the case for security reasons on CORS error. The 'ResizeObserver loop' error shouldn't cause an artificial CORS error.
The ResizeObserver error appears to be an uncaught exception, and some JavaScript code (possibly in window.onerror) reports it. There is no evidence of a browser engine bug here, this all looks normal. The link displayed by the handler (https://blog.sentry.io/2016/05/17/what-is-script-error) has some reasonable looking explanation too.
(In reply to Alexey Proskuryakov from comment #1) > The ResizeObserver error appears to be an uncaught exception, and some > JavaScript code (possibly in window.onerror) reports it. There is no > evidence of a browser engine bug here, this all looks normal. > > The link displayed by the handler > (https://blog.sentry.io/2016/05/17/what-is-script-error) has some reasonable > looking explanation too. Initially, the issue is, why does 'cross-origin' error occur on ResizeObserver loop?