Created attachment 177353 [details]
Screenshot made during the freeze (task manager still in animation)

SUMMARY

On a vertical screen with a narrow default panel, opening the panel configuration caused the task manager to alternate between single and multi row view rapidly thus making the other parts of the shell unresponsive.

STEPS TO REPRODUCE

1. Have some distinct tasks open
2. Set the default panel's width to "Fit content"
3. On the same panel, have an icons only task manager and set the multi-row view to "When panel is low on space and thick enough"
4. Change the panel width by opening the panel configuration

OBSERVED RESULT

The task manager alternates between single and multi-row view and the rest of the shell won't respond

EXPECTED RESULT

The task manager chose either single or multi-row view and stays like that

SOFTWARE/OS VERSIONS
OS: Arch Linux
KDE Plasma Version: 6.2.5
KDE Frameworks Version: 6.10.0 
Qt Version: 6.8.1
Graphics Platform: Wayland

ADDITIONAL INFORMATION

Reproduced on a vertical screen, when the freeze happens, quickly changing session and back (Ctrl+Alt+F<1-12>) may help opening a terminal if needed (found by accident). Note that `plasmashell --replace` may not work because the shell will be frozen at the time.