VLC Media Player steals focus on mouse-over.
This bug has been driving me mad for years and it never seems to get fixed, so I'm going ahead and submitting a bug report for it.
Whenever I have VLC Media Player playing a video in fullscreen mode, and then I Alt+Tab to another program (such as my web browser, but it could be anything), roughly 80% of the time if I move the mouse back over VLC Media Player, it instantly steals the focus, taking me away from whatever I'm trying to do in the other program. It's extremely irritating as it happens so much!
I then have to Alt+Tab back to it, and then as I move my mouse to work in that other program, it goes over a single pixel of VLC and it steals focus yet again. It's an evil cycle and to work around the bug I have to specifically place my mouse in the area where the the other program will appear -before- Alt+Tabbing to it, and then be very careful to never move the mouse outside of that window. Frustrating!
Operating system: Windows 7 Professional 64-bit.