Firefox dropdown menus are flickering on 2nd monitor
Had a very weird problem with Firefox on my Windows 7 box. (It might also happen on Ubuntu desktop.) I switched the connection on my second, extended desktop monitor to use DVI instead of VGA. Suddenly, all the Firefox drop-down menus went blank. They would flicker briefly and I could see the contents, but then they would go blank.
For example, when typing in a URL in the Firefox wonderbar, I get a code completion drop down list with all matching URLs and locations I’ve recently visited. The drop down list is there and appears for a split fraction of second, but then it goes blank and I can’t see it. It’s just a big blank rectangle. Oddly, I can select items from it and they appear in the wonderbar, but I don’t see them until I select them and all remaining items remain blank.
The same thing happens for the search box, some Firefox menus, etc.
The Solution: Turn off Firefox Hardware Acceleration
Got to the Firefox Options –> Advanced tab –> General tab. In the “Browsing” section uncheck the box marked “Use hardware acceleration when available”
Cha-ching!!! Problem solved.