#1135797 xfwm4: flooded GLib-CRITICAL when using external compositor (Picom)

Package:
xfwm4version: 4.20.0-1severity: normaltags: patch
Source:
xfwm4version: 4.20.0-1severity: normaltags: patch
Submitter:
geazzy astria
Date:
2026-05-06 01:25:02 UTC
Severity:
normal
#1135797#5
Date:
2026-05-06 01:23:09 UTC
From:
To:
Package: xfwm4Version: 4.20.0-1Severity: normalTags: patch
Dear Maintainers,
I've encountered a regression in xfwm4 where the ~/.xsession-errors log is flooded with the following error whenever switching windows while using an external compositor (Picom):
(xfwm4:20982): GLib-CRITICAL **: g_hash_table_lookup: assertion 'hash_table != NULL' failed
This is due to xfwm4 attempting to look up a window in 'cwindow_hash' which remains NULL when an external compositor is active.
I have confirmed that this is fixed in the upstream master branch via this commit:https://gitlab.xfce.org/xfce/xfwm4/-/commit/69a16352
I have manually compiled xfwm4 with this patch on my system and can confirm it solves the issue. Could you please consider cherry-picking this patch for the current Debian package?
Best regards,