Dear Maintainer,

Application: dolphin (22.12.3)

Qt Version: 5.15.8
Frameworks Version: 5.103.0
Operating System: Linux 6.1.0-23-amd64 x86_64
Windowing System: X11
Distribution: Debian GNU/Linux 12 (bookworm)

Dolphin crashing typically after desktop system goes idle and is fairly
repeatable.

I tried installing packages with debug symbols via this guide
https://wiki.debian.org/HowToGetABacktrace but was unsuccessful in creating a
more meaningful backtrace.

I'm also running the same version of Dolphin on a laptop so I am suspecting it
is possibly related to an external drive going idle.

The crash can be reproduced every time system is idle for an extended period of
time.

Control: reassign -1 libqt5gui5 5.15.8+dfsg-11+deb12u2
Control: affects -1 + dolphin


Hello Cody,
I am not maintainer of dolphin or Qt packages,
but I have reason [1] to believe this crash is the same
which I received already some time ago here:

https://bugs.kde.org/show_bug.cgi?id=461723

Unfortunately this led first to Qt, and there got something changed,
which even made its way into Debian, but sadly this did not solve the issue:

https://bugreports.qt.io/browse/QTBUG-109226
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1025997


Later the KDE bug report got handled as a duplicate of this KDE bug:

https://bugs.kde.org/show_bug.cgi?id=473602

There was some more discussion and two merge requests:

https://invent.kde.org/plasma/kwin/-/merge_requests/4388
https://invent.kde.org/plasma/kwin/-/merge_requests/4590

The latter got merged upstream and I think it might solve the issue.


Unfortunately I grown a habit to not maximize windows of
Qt based applications, therefore I lost track of this issue...

Usually I received this crash when changing display resolution,
or when waking up the monitor after I left the computer.
Also this is highly timing related, so it does not happen all the time
and not to all full screen windows.



To be sure this are the same issues you could install
the package libqt5gui5-dbgsym, and generate another backtrace?
Maybe you have still stored one? coredumpctl list


Maybe you could also confirm these assumptions:
- You have connected multiple monitors?
- The dolphin window was full-screen when it crashed?
- Did it happen when you left the computer and tried to wake it up?


Kind regards,
Bernhard



[1] (the addresses in the backtrace without symbols could match these locations)
0x00007ffff01dd14a in copy_unswapped at ./src/plugins/platforms/xcb/qxcbbackingstore.cpp:545
0x00007ffff01dd749 in QXcbBackingStoreImage::flushPixmap(QRegion const&, bool) at ./src/plugins/platforms/xcb/qxcbbackingstore.cpp:628
0x00007ffff01de089 in QXcbBackingStore::flush(QWindow*, QRegion const&, QPoint const&) at ./src/plugins/platforms/xcb/qxcbbackingstore.cpp:879
...
0x00007ffff01e7eca in xcbSourceDispatch(GSource*, GSourceFunc, gpointer) at ./src/plugins/platforms/xcb/qxcbeventdispatcher.cpp:106
...

A bit of an update,

I did a reinstall of Debian with KDE and noticed no crashing of plasma at all until I added this to my kwinrc file:

[Windows]
BorderlessMaximizedWindows=true

I am fairly certain this is the culprit. Again, plasma does not crash on my laptop even when using this setting.