Created attachment 142698 [details]
KWin app switcher truncation

SUMMARY
Given only a few windows open but with large title text, "Large Icons" task switcher sometimes fails to truncate extra long titles, and the text effectively overflows the width of the switcher.

I noticed that it does not affect the first window in a task switcher's row. It is also a "sticky" glitch: once activated, the text of that particular window will keep overflowing in the Alt+` menu, and won't go away despite switching between windows of the same app. It will, however, reset upon switching back and forth between different apps.

STEPS TO REPRODUCE
1. Open at least 2 windows of the same app with long titles.
2. Alt+Tab to another app, and switch back.
3. Hold Alt, and press ` repeatedly to cycle through windows of that app from step #1.

OBSERVED RESULT
Sometimes the title text will be so long that it should truncate with ellipsis, but instead it just overflows and gets cut at edges.

EXPECTED RESULT
Truncation should always work.

SOFTWARE/OS VERSIONS
Operating System: Arch Linux
KDE Plasma Version: 5.23.80
KDE Frameworks Version: 5.88.0
Qt Version: 5.15.2
Kernel Version: 5.14.12-arch1-1 (64-bit)
Graphics Platform: X11
Processors: 8 × Intel® Core™ i7-6700HQ CPU @ 2.60GHz
Memory: 15.6 GiB of RAM
Graphics Processor: NVIDIA GeForce GTX 970M/PCIe/SSE2

ADDITIONAL INFORMATION