[BUG] Window list sometimes omits entries from second screen

[FriedrichFroebel]

 * Cinnamon version 5.4.10, installed from the official packages
 * Distribution: Mint 21
 * Graphics: Intel 2nd Generation Core Processor Family Integrated Graphics (from Intel Core i5-2520M)
 * 64 bit

Issue

I updated to Linux Mint 21 one week ago and just applied the latest Cinnamon update again (from 5.4.9 to 5.4.10). For some reason in both cases the applications being displayed on the second screen have been missing from the window list afterwards. As soon as I moved them to the primary screen, they showed up again; they would hide again as soon as I moved them to the second screen.

Forcing a Cinnamon restart fixed this, although this is no practical solution. On the other days, this issue has not been present, leading me to the assumption that this indeed might be related to the corresponding updates.

Steps to reproduce

• Update Cinnamon.
• Move window to second screen.
• Move window to primary screen.

Expected behaviour

The window list will always display the corresponding window.

[JulianGro]

Same issue here:

 * Cinnamon version (cinnamon --version) - 5.4.10
 * Distribution - Debian Testing
 * Graphics hardware *and* driver used - Nvidia GTX 1080 with Nvidia proprietary 470.141.03
 * 32 or 64 bit - amd64
 * Attach ~/.xsession-errors, or /var/log/syslog 

xsession-errors.txt

Issue

When moving a window to a different display, it disappears from the task bar.

Steps to reproduce

• Connect second display.
• Drag window over
• Window disappears from the task bar

Expected behaviour

Window should not disappear from the task bar. At least not if the second display has no task bar of its own.

Other information

I am using the window-list@cinnamon.org instead of the default grouped list.
While I don't remember this being an issue before, I also don't see an cinnamon update in my history.

[lzbk]

While I don't remember this being an issue before, I also don't see an cinnamon update in my history.

For me it started with Mint 21 upgrade

[shavounet]

Reproduced on Mint 21 too, changing the principal screen temporarily fixed it