no function on [Alt] [F2] ... [F6]

[Ulli Horlacher]

I liked the window actions on [Alt] [F2] ... [F6] - but now they are gone.
When I hit these key combinations nothing happens.
Only [Alt] [F10] and [Alt] [F11] are still working
I suspect, I have misconfigured it. 
How can I restore these default window action keys?


-- 
Ullrich Horlacher              Server und Virtualisierung
Rechenzentrum TIK         
Universitaet Stuttgart         E-Mail: horlacher at tik.uni-stuttgart.de
Allmandring 30a                Tel:    ++49-711-68565868
70569 Stuttgart (Germany)      WWW:    http://www.tik.uni-stuttgart.de/
REF:<20181228005943.GA13455 at tik.uni-stuttgart.de>