Version:           unspecified (using KDE 4.4.4) 
OS:                Linux

Hi ! (sorry for my bad english)

I'm using KDE SC 4.4.5 and one nvidia 8600 GT videocard with 2 screens (LCD+TV) on twinview mode. nvidia driver is installed and works fine.

I'm using taskbar widget for see my actives applications and for reduce (with left clic on applications buttons) them.

I'm using kaffeine on my second screen (TV) for see videos.

But I have got a problem since a long time under KDE 4.x....

when I see a video, with kaffeine, in full screen mode, on my second screen, I can't reduce my others applications, with left clic, on a first screen, in taskbat widget. I can clic several times on applications taskbar button without effect...

if I change my video of "full screen mode" to "window mode", I find back the good working of taskbar.

Reproducible: Always

Steps to Reproduce:
- nvidia videocard with nvidia driver
- 2 screens on twinview mode
- KDE SC 4..4.5
- launch dolphin in first screen
- launch a video, with kaffeine, in full screen mode, on second screen
- try to reduce dolphin with taskbar dolphin's button

nop, niet :-/

- for video, on second screen, change a video mode "full screen mode" to "window mode"
- try to reduce dolphin with taskbar dolphin's button

it's works !

Actual Results:  
problem existing since a long time under KDE 4.x


I don't test with other videoplayer