I have not understood why I can not easily find a way how to report a bug with a core dump (.zst file) in private, since per my understanding, these files can contain sensitive data.
So how to do it please? I am on Debian 12 and currently having problem with latest stable kwin:
SIGABRT present /usr/bin/kwin_x11 962.6K
Somewhat related - Debian 12 is using an outdated version of KDE Plasma / KWin (5.27.5, released in May 2023), omitting several months’ worth of patches to Plasma 5.27 and definitely not using the currently developed version 6.2, so it’s possible that what you’re experiencing is specific to the version of Plasma that Debian has intentionally frozen on, or the way in which Debian has packaged that together.
It’s likely worth going through Debian’s bug reporting process first: