Thanks @bigrodg66 @chetbanach @pitpat6 @mspacek for the feedback
I have one dump from forum user @Olli for the STACK_BUFFER_OVERRUN crashes (Exception Code 0xc0000409) - This has been referred to the development team with the associated logs
May help to get more examples of these crashes - it would need a registry change to make windows capture the application crash dumps
See registry edit on this support article:
Crash Logs: Plex Media Server | Plex Support
After making the registry edit, please create this folder if it does not exist
%LOCALAPPDATA%\CrashDumps
and ensure debug logging is enabled in Plex Media Server - see Reporting issues with Plex Media Server | Plex Support
Restart Windows and on next crash capture the server logs and look for a dump file under %LOCALAPPDATA%\CrashDumps - zip and upload on google drive or dropbox etc and send me link privately and make the related debug server logs available
Thanks