I was in the process of installing "Additional Drivers" when I encountered an error and I was informed to review a log. I left the notification dialog open while I switch to a terminal but when I switched back, the notification dialog was missing/hidden, now the primary dialog won't close. I can't find the hidden notification dialog even if I minimize everything nor can I find the process PID that the dialog box belongs to? In even likes these, what can I do?
In terminal (open a terminal window with CTR+ALT+T)
This will kill all processes that have that phrase in the title
pgrep returns the pid # number of a process that you know the name of.