User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b8pre) Gecko/20101210 Firefox/4.0b8pre Build Identifier: With Aero and the Firefox button enabled the area to resize the main window is much smaller than those of standard windows applications. In standard window applications, you have a tolerance of around 16 pixel left/right, but with Firefox you have to hit exactly the edge. Reproducible: Always Steps to Reproduce: 1. Move cursor to bottom right window edge 2. Move cursor a few pixels to the left Actual Results: Cursor changes to up/down resizer. (↕) Expected Results: Cursor should stay diagonal. (top-left to bottom-right)

I added a screenshot to make clear what I'm talking about. Normal windows show a NW-SO cursor in the range of the green area, Firefox does this only in the red area.

Requesting blocking as it is a regression and a small hit target of around 8x8 pixels is clearly not enough for such an important thing like resizing a window.

Jim, do you know which code is responsible for this?

Yeah, that's right here: http://mxr.mozilla.org/mozilla-central/source/widget/src/windows/nsWindow.cpp#5803 We base it on some system metrics related to the sizing area. I see a slight difference between fx and notepad for the lower and upper borders. Should be easy to tweak. I'll take a look this week.

Looks the bottom border is the only one that gets extended, and based on a simple measurement, it appears to be twice the margin size. Felipe, care to take this for a spin and review?

Comment on attachment 505259 [details] [diff] [review] patch Nice, I never noticed this detail on Windows before. It definitely helps on resizing

Verified fixed in Mozilla/5.0 (Windows NT 6.1; WOW64; rv:2.0b12pre) Gecko/20110204 Firefox/4.0b12pre