endSessionDialog prematurely closes Qt applications.
Launching endSessionDialog, either from panel menu, or by pressing the hardware power button, instantly closes every Qt4 and Qt5 based application I've tested, i.e. they are closed before user clicks 'Shutdown' or 'Reboot'.
I've only noticed this behavior after 3.28 update, so I suppose something broke during that cycle. I got some logs from avidemux3_qt5, and it simply reports 'Close event!' when this happens, and exits cleanly.