Every so often okular stops working. I click an attachment in email, an icon blinks on the taskbar, then it disappears.
ps aux | grep okular shows it is running. I run
killall okular, checks that none are running, and try again. same problem.
I start okular from command line (konsole), nothing happens.
Here's the interesting part:
In konsole, I become root
su - then try to run okular. It works!
Restarting the system make the problem go away ... until next time.