SUMMARY When an application (can confirm with firefox and OBS window) is set to autostart, and floating panel is placed on top of the screen, after login, the app (assuming it was maximized) opens maximized (expected) and the panel immediately de-floats but the top portion of the titlebar gets hidden behind the panel (i.e the maximized window goes a little under the panel). Minimizing and maximizing again (or restore to window mode and maximize again) fixes the issue as the panel floats and de-floats once. STEPS TO REPRODUCE 1. Set an app to autostart 2. Make sure the app is maximized so it'll open maximized after login 3. Set panel to floating mode and move to the top of screen 4. Logout-login or reboot, wait for the autostarted app to open 5. Desktop loads, floating panel loads, gets de-floated as the autostart app opens maximized 6. Titlebar gets a bit 'under' the panel OBSERVED RESULT Titlebar gets under/cutoff by the top de-floated panel EXPECTED RESULT The window should fit (or maximize) only till the panel, not go under it. SOFTWARE/OS VERSIONS Operating System: Fedora Linux 40 KDE Plasma Version: 6.1.3 KDE Frameworks Version: 6.4.0 Qt Version: 6.7.2 Kernel Version: 6.9.10-200.fc40.x86_64 (64-bit) Graphics Platform: Wayland Processors: 4 × Intel® Core™ i5-6300U CPU @ 2.40GHz Memory: 11.1 GiB of RAM Graphics Processor: Mesa Intel® HD Graphics 520 Manufacturer: HP Product Name: HP ProBook 640 G2
Just realised, this might indeed be linked to another report I made here: https://bugs.kde.org/show_bug.cgi?id=490959 The amount of titlebar that gets hidden behind the panel for autostart apps seems to exactly the same amount by which a maximizing window overshoots when the panel defloats, as mentioned in the other bug report. I'll link the screen recording again, that I posted there: https://imgur.com/a/eYvDS03 Notice how the window goes under the panel for a moment? With autostart apps (this specific report), the maximized window does exactly that but never resizes back, the top portion of the titlebar gets permanently hidden behind the panel until the window is minimized/restored to floating window and maximized back.
This has been fixed by a big refactor of floating panel code in Plasma 6.2. Thanks for reporting it!