Ooh, nice catch! I tested this and found the same behavior on my Windows problem PC: re-enabling the system tray icon and "close to system tray," then using the system tray icon to select "Quit Fluxer," will close the program successfully and stop all processes immediately. As soon as I disable the system tray icon again, the processes fail to terminate when the program is closed.
I can reproduce this as well. Could you edit your report to reflect these new findings, and also remove the Win10 tag since this seems to affect other platforms? I can confirm this once that's done.
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Comment by Adam Novagen
Comment by Fullest
Comment by Adam Novagen