Don't think it's the same as the bug linked as it's not on startup, it's when taking a screenshot. I thought I couldn't reproduce it, but I can if I:
Click "Grab the current window"
Click on Firefox 3.0.6 to focus it (can reproduce with any window though, like a terminal)
Click on the Take Screenshot button (the window is not behind anything so I can click straight on the button)
Whole-window screenshots are always fine, and it doesn't crash if I uncheck the "Window border" checkbox... but I've noticed that if I do that, it doesn't actually take a screenshot of the Firefox window, it takes a shot of the top left 296x284 px of the screen. It is given the filename Screenshot-Untitled Window.png.
If I put a 1 second delay on the capture, then it always works; though it doesn't have a window border.
I'm running Compiz with TwinView. It feels like Compiz could be the cause - when it captures a small box in the top-left, it looks roughly the size of the screenshot dialog, as if it's using that as the current window, which might explain why the 1 second delay fixes it (allowing the Compiz close animation to finish and transfer focus).
Don't think it's the same as the bug linked as it's not on startup, it's when taking a screenshot. I thought I couldn't reproduce it, but I can if I:
Click "Grab the current window"
Click on Firefox 3.0.6 to focus it (can reproduce with any window though, like a terminal)
Click on the Take Screenshot button (the window is not behind anything so I can click straight on the button)
Whole-window screenshots are always fine, and it doesn't crash if I uncheck the "Window border" checkbox... but I've noticed that if I do that, it doesn't actually take a screenshot of the Firefox window, it takes a shot of the top left 296x284 px of the screen. It is given the filename Screenshot-Untitled Window.png.
If I put a 1 second delay on the capture, then it always works; though it doesn't have a window border.
I'm running Compiz with TwinView. It feels like Compiz could be the cause - when it captures a small box in the top-left, it looks roughly the size of the screenshot dialog, as if it's using that as the current window, which might explain why the 1 second delay fixes it (allowing the Compiz close animation to finish and transfer focus).
Hope that helps.