Bug 500109

Created attachment 178391 [details]
The gap that appears when an app is closed.

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SUMMARY
The Icons-Only Task Manager is surprisingly sluggish to notify KWin of changes in the amount of space it needs, resulting in noticeable gaps.

STEPS TO REPRODUCE
1. Create a panel with the Icons-Only task manager that fits itself to its content.
2. Open an application that is not pinned to the task bar.
3. Close that application

OBSERVED RESULT
A gap opens up in the Panel that requires the panel be updated to disappear.

EXPECTED RESULT
The Panel should immediately resize upon the app disappearing from the Taskbar.

(available in the Info Center app, or by running `kinfo` in a terminal window)
Linux/KDE Plasma: CachyOS Linux
KDE Plasma Version: 6.3.0
KDE Frameworks Version: 6.10.0
Qt Version: 6.8.2

ADDITIONAL INFORMATION
This seems to be a regression, as this was not an issue in Plasma 6.2.5