Got into strange situation yesterday.
I was poking some exotic key-compinations like alt+everything and ctrl+everything and <super>+everything, as suddenly all windows wanished. Whatta..!?
It turned out, that it was <super>+S that stopped my current activity. But as I’m not acivity-user nor fan of it (virtual desktops are good and enough for me) I wasn’t sure what I see or what I can do. Opening Konsole I saw, that my processes were still running, so it wasn’t some mysterious X- or gpu-crash.
As I suspected, some activity trick it might be. I removed one as I had two of them. Nothing. Then I changed task-manager, that it would show windows from other activities. YESS… there they were, but ofcourse – not usable.
Hardcore
You think, that you could find some mythical options like:
* transfrer all windows from other activities to current one? No!
* Move all windows to… ? No!
* Eerm.. fix activity state? No 🙁
* Would relogin or restart fix it? No :((
So I removed for first thing activity* files from .kde4/share/config. No help. But then, as programmer I thought, that there should be some relation between objects “activity” and “window”.. and seemed that .kde4/share/config/kwin… file contained it. Deleted it and after relogin – GREAT SUCCESS! All session-saved windows were back to default activity.
Day is saved again.