With both displayfusion v.3.4.0 and v.3.4.1 I'm experiencing an extremely slowdown of the UI responsiveness whenever I have a Firefox 9.0.x window open on the *secondary* screen. Scrolling is literally taking ages and you can see the repainting flicker alot. If I drag the Firefox window to the primary screen, performance is normal. To make things bizarre, I'm seeing this enormous slowdown only for Firefox but not for other programs, such as an PDF viewer or the MS office suite.

I've enabled the (simulated) taskbar on the secondary screen. The system is a Fujitsu notebook with an i5 CPU M520/2.4GHz, 3GB RAM, and integrated Intel HD Graphics controller. Just to emphasize: graphics performance is perfect on the primary screen, but heavily sucks on the secondary screen -- just for Firefox (at least I'm not aware of another program with the same problems at this time).

Any suggestions as to what may cause this sluggish behavior?

No, unfortunately not. Performance stays the same with and without the Multi-Monitor taskbar.

I'm not sure whether there is some bad interaction between Firefox' Cairo UI engine and DisplayFusion? But why does this then happen only on the secondary monitor and not on the primary one? Strange!

Keith,

you are right and I could have checked that myself before asking for help here: the performance problems is still there even if I exit DisplayFusion (Pro). So this points towards an Intel graphics driver problem.

Thank you very much for your support!
-- Harald