SUMMARY
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if i reboot my laptop from plasma start menu, battery icon goes missing. not just from the panel but it is completely gone from tray too, i can't see it even if i expand the tray. however, if i shutdown and then boot, this problem doesn't occur.
NOTE: If you are reporting a crash, please try to attach a backtrace with debug symbols.
See https://community.kde.org/Guidelines_and_HOWTOs/Debugging/How_to_create_useful_crash_reports
***

STEPS TO REPRODUCE
1. reboot via plasma session menu
2. login

OBSERVED RESULT
battery icon is missing from tray

EXPECTED RESULT
battery icon should stay after reboot

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Debian 11 Bullseye (current stable), Linux 5.10.0-9-amd64
KDE Plasma Version: 5.20.5
KDE Frameworks Version: 5.78.0
Qt Version: 5.15.2

ADDITIONAL INFORMATION
happens both on arch linux and debian 11 bullseye (stable)