On Tue, Jun 28, 2016 at 05:19:08AM +0200, Michał Mirosław wrote: > I just tripped on this bug when launching 'xscreensaver-command -lock' from > xmobar's label action. Locking via shell-script with 'sleep 0.1' before > xscreensaver-command works around this problem.
Ah. The delay has to be greater than button press time. It looks like the command is executed on ButtonPress event and not ButtonRelease. Maybe this interacts badly with (just guessing) drag-n-drop or something?