This is a new one I haven’t experienced yet, as I usually leave my system in performance mode when at home. I went out, didn’t have an outlet nearby to plug in to charge, and selected power save mode. Later, when I selected performance mode, system immediately crashed (not sure if this is relevant, but the caps lock key’s light begins flashing).
Power save mode works just fine.
I’ve tested and this happens on both the LTS (6.1.69) and mainline (6.6.8) kernels when selecting performance mode.
Thinkpad T480
KDE version 5.27.10