SUMMARY Quick tiled windows are temporarily being resized to (nearly) 0x0 when switching monitors. Afterwards the window is automatically being resized to it's correct size. This is a regression between KDE 5.20.5 (working fine, Debian-11) and 5.27.5 (Debian-12). Unfortunately even temporarily resizing to 0x0 confuses some UI toolkits like Gtk-3. In case of Gtk-3 the window content is not being rendered any more, even after resizing the window back to a valid size. Resizing to 0x0 doesn't seem to happen with every hardware. But the same problem is reproducible when simply turning off all displays for a moment. xrandr --output DISPLAY_NAME --off; sleep 3; xrandr --output DISPLAY_NAME --auto STEPS TO REPRODUCE You may reproduce this with a Debian-12, Kubuntu-23.10 or openSUSE-15.5 live image in a VM. https://download.opensuse.org/distribution/leap/15.5/live/openSUSE-Leap-15.5-KDE-Live-x86_64-Media.iso There you need to install a Gtk-3 application like "Geany" or "Pavucontrol". Debian/Kubuntu: sudo apt update; sudo apt install geany SUSE: sudo zypper install geany 1. Start Geany and move it to the middle of the screens left boarder to trigger quick tiling. (tiling it into a corner won't trigger the bug) 2. Close Geany and reopen it. (Don't ask me why this is needed. But else the bug doesn't happen.) 3. On reopening Geany should have opened tiled to the left half of the screen. 4. Disconnect the display for a moment, then reconnect it. Alternatively run: xrandr --output DISPLAY_NAME --off; sleep 3; xrandr --output DISPLAY_NAME --auto 5. Press CTRL+w to close the file opened in Geany. You'll see the window title changing, so Geany didn't completely crash. But the content of the window stays frozen. You may press CTRL+n to open a new empty file and the window title, the window title will change again, but the window content will stay frozen. This overrides the minimum window size set by Geany and Pavucontrol which is somewhere around 50x50. The same effect can be achieved by forcefully resizing Geany to 1x1. Simply right click the window titlebar, choose More Actions -> Configure Special Window Settings -> Add Property -> Size There you set "Force", 1x1 (0x0 doesn't work here) and cilck "Apply". Afterwards change the value to 500x500. OBSERVED RESULT Window gets temporarily resized to (somewhere nearly) 0x0. EXPECTED RESULT Respect minimum window size. Or simply don't touch the window size at all when there's no active display anyway. SOFTWARE/OS VERSIONS Linux: Debian-12 KDE Plasma Version: 5.27.5 KDE Frameworks Version: 5.20.5 Regression: 5.20.5 on Debian-11 was working fine ADDITIONAL INFORMATION May be related to this bug: Split does not reset to its original value once "adjacent quick-tiled windows" configuration ceases to exist https://bugs.kde.org/show_bug.cgi?id=465937 Window placement and positioning are sometimes wrong when waking up from sleep https://bugs.kde.org/show_bug.cgi?id=465937 (sleeping may also "hide" the displays temporarily on some hardware)
What Plasma versions do Kubuntu 23.10 and OpenSUSE 15.5 use? Debian is very out of date with 5.27.5; the bug you're describing should be fixed in 5.27.11, so if the other distros don't ship that yet, they'd still be affected as well
(In reply to Zamundaaa from comment #1) > What Plasma versions do Kubuntu 23.10 and OpenSUSE 15.5 use? Debian is very > out of date with 5.27.5; the bug you're describing should be fixed in > 5.27.11, so if the other distros don't ship that yet, they'd still be > affected as well https://cdimage.ubuntu.com/kubuntu/releases/23.10/release/kubuntu-23.10-desktop-amd64.manifest (2023-10-10) kwin-x11: 5.27.8 plasma-workspace: 4:5.27.8 (reproduced bug) https://download.opensuse.org/distribution/leap/15.5/live/openSUSE-Leap-15.5-KDE-Live-x86_64-Build13.15-Media.iso Plasma: 5.27.9 (reproduced bug) Kubuntu 24.04 Beta: https://cdimages.ubuntu.com/kubuntu/daily-live/current/ (2024-03-26) kwin-x11: 5.27.10 plasma-workspace: 5.27.10 (reproduced bug) I've checked the Plasma versions in Manjaro (2024-01-13) and Debian-13-Testing (Beta 2024-03-25). (just checked Plasma version, didn't try to boot and reproduce the bug) At maximum there was Plasma-5.27.10. It looks like Plasma-5.27.11 is still too young to be shipped with any distro. https://invent.kde.org/plasma/kwin/-/tags/v5.27.11 (2024-03-06) https://invent.kde.org/plasma/kwin/-/tags/v5.27.10 (2024-12-05) And KDE-Neon already ships Plasma-6.0.2. So I compiled kwin-5.27.11 and kdecoration-5.27.11 (needed dependency). And this fixed the bug :-) Debian-12: mkdir -p ~/opt/kwin/build/ cd ~/opt/kwin/build/ wget https://invent.kde.org/plasma/kwin/-/archive/v5.27.11/kwin-v5.27.11.tar.bz2 wget https://invent.kde.org/plasma/kdecoration/-/archive/v5.27.11/kdecoration-v5.27.11.tar.bz2 tar xf kdecoration-v5.27.11.tar.bz2 tar xf kwin-v5.27.11.tar.bz2 cd kdecoration-v5.27.11 mkdir build cd build cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_TESTING=false -DCMAKE_INSTALL_PREFIX="${HOME}"/opt/kwin .. make -j$(nproc) install cd ~/opt/kwin/build/kwin-v5.27.11/ mkdir build cd build cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_TESTING=false -DCMAKE_INSTALL_PREFIX="${HOME}"/opt/kwin .. make -j$(nproc) install ~/opt/kwin/bin/kwin_x11 --replace
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