When I installed suse, scrolling in firefox was really laggy(<20 fps) on my 1920x1200 monitor and hd 4200 igp. After playing with some system settings, I realized that smooth scrolling was on by default in Firefox 4. Disabling it made firefox useable as a browser.
My question is why the suse engineers would do such an idiotic thing. The setting is turned off by default for a reason on all of the firefox channels, so it's stupid for a distro to enable the feature, especially when it reduces system useability.
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I'm on openSUSE 11.4 too, and Firefox (with smooth scrolling on, I assume) works fine for me. But then, that may be just me. I have a 1280x1024 monitor with a 8400GS.