I've had problems with WB and Firefox since Firefox switched to the "unibar" layout a while back. If I try to use FF with the skin, it just keeps flickering and is completely unusable - my guess is WB is trying to skin a non-existent titlebar. Never had any problems with WB and Thunderbird though.
Oldiesmann
I'm also having problems setting up my avatar. In IE, it appears to upload it (for about 2 seconds or so), but no image ever appears. In Firefox and Chrome, I just get a cryptic error message (Upload Error, Code: 200, Message: -600, followed by something saying the upload will be canceled and to please try again). The image I'm trying to upload is less than 5kb in size and was converted to png from gif using Paint .NET. I have also tried a jpg version (also converted from gif
Not sure if this is a known problem, but the latest beta of Firefox 4 (Beta 5) breaks WindowBlinds compatibility again. I have to tell WindowBlinds not to skin Firefox or it doesn't work properly (hard to explain here, but it's easy to see what the problem is when you try to use FF4b5 with WB). I didn't have any problems with Beta 4 and WindowBlinds, so it must be something that changed with Beta 5. Edit: It seems to be related to the new DirectX 2D graphics acceleration featu