Created attachment 6626 Uniform white region (from the very bug submission page) screenshotted Doesn't always happen, but when it does, more layers of it seem to happen if the mouse is moved back and forth while held.
As I mentioned in 12629, the select region mode currently has no delay to capture the screenshot after releasing the mouse button. In my GTK3 Port I introduced a 1sec delay to avoid this problem.
I cannot reproduce with 1.9.1 anymore (thanks to the 1sec delay).