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[FIXED] AccordionLayout issue in FireFox
Have you noticed the flicker when using Accordino layout in FirFox? You can see this in your own demo "GWT 2.0 Desktop" under Accordion Window, when you switch between the tree and other panels, there is a flicker.
I noticed the same when I updated our application from 1.2.4 to 2.0.0. I fixed this simply by setting setAnimCollapse(false) for each panel inside the accordion.
The problem is the overflow at the tree. As the overflow can be at any level deepth, it is quite hard to fix this in FF.