Comment 47 for bug 481656

I'm also affected by this on 14.04 with IDEA's IntelliJ. I used to see it on older releases as well.
"ibus restart" helps to kick things back into cooperation.
It's hard to reproduce; I would say it happens about 5 times per week on average, but on a bad day I can get it several times in a matter of an hour or so.

Keyboard input never gets lost halfway typing something, but always right after a bit of window/desktop switching. I always switch windows/desktops using keyboard shortcuts (alt-tab for windows, ctrl-alt-j/k for desktops). During those I often hit Alt or Super by accident, opening the HUD or the launcher respectively. I have a strong feeling, but am not 100% certain that those are involved as well.