Created attachment 437696 [details]
Copy of the failing packet listing from the Safari Web Inspector (Monterey)
We are experiencing unexplained Websocket connection failures/closes when connecting to our servers on macOS Monterey.
Specifically larger message payloads, after a series of smaller messages are able to reliably reproduce the issue.
I've attached the larger messages which cause the issue.
This is not an issue on macOS Big Sur and earlier.
Created attachment 437697 [details]
Copy of successful packet listing from BigSur
If credentials etc, are needed to help diagnose this issue I can happily provide them via private mail.
I reached out for those credentials.
Thank you for writing this bug and giving me access to your test setup. It allowed me to isolate the cause of this bug and find a fix.
I isolated it to some valid UTF-8 sequences being flagged as invalid, which causes kNWErrorDomainPOSIX error 100
*** This bug has been marked as a duplicate of bug 228296 ***