I noticed that many times already, most of our systray icons behave fine when changing the monitors bpp via desk.cpl.
But the power icon has problems and is not painted anymore when I change the bpp from 32bpp to 24bpp
initially drawn correctly with 32bpp 32bpp_ok.png
But after the switch to 24bpp it does not draw. 24bpp_wrong_not_painted.png
If I restart the explorer.exe with 24bpp then it draws properly.
So we most likely must just handle some windows-message for this stobject.
ftr the (win32ss/user/ntuser/windc.c:749) err: [0002015A] GetDC() without ReleaseDC()!
is unrelated happened after the bug, and is from closing desk.cpl (that part is fixed in master head already. Just not yet in the 0.4.14RC).