SUMMARY
***
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***


STEPS TO REPRODUCE
1. Add two flexible spacers on both sides of icon only task manager. Add global menu between kickoff and first spacer.
2. Have little free space on panel (add many (12-13) apps to icon only task manager).
3. Make icon only task manager single row.
4. Minimize and maximize 2nd last active task entry while last icon is an active task

OBSERVED RESULT

Last (few) icons fly in and out, sometimes disappears totally.

EXPECTED RESULT

All icons remains visible.

SOFTWARE/OS VERSIONS
Operating System: KDE neon Unstable Edition
KDE Plasma Version: 5.26.80
KDE Frameworks Version: 5.101.0
Qt Version: 5.15.7
Kernel Version: 5.18.7-200.fc36.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 8 × Intel® Core™ i7-10510U CPU @ 1.80GHz
Memory: 7.4 GiB of RAM
Graphics Processor: Mesa Intel® UHD Graphics

ADDITIONAL INFORMATION

Demonstration (video): https://diode.zone/w/hchVkmfm7jDzKXRfBDPQ9b

Also happens in current stable version and also on fedora (hardware). The demonstration here is produced in clean and latest neon docker developer edition.