I trigger this bug surprisingly often. Steps to reproduce: - Press Alt+F2. - Type the first few letters of a program's name and hit enter, all done extremely quickly (say, less than 100 ms). Expected results: Program launches same as if I had typed it slowly. Actual results: krunner remains open and does nothing. Enter keypress gets ignored because the completion didn't appear in time. Proposed solution: Record a timestamp whenever the enter key is pressed on no suggestions. When a suitably good match to the search string is later found, if enter was pressed less than 200 ms ago then pretend enter had just been pressed.
This is just because the runner results take a little bit of time to appear. KRunner should now show up faster anyway: BUG 416145 and if that is not good enough you can disable some plugin. Don't forget to restart KRunner, see also BUG 421426. Emitting the key-press later seems kinda weird, especially considering that we would run a match which the user hasn't seen.