This is going to be difficult to explain, so I'll do my best; Recently, Firefox has been exhibiting a problem where, upon maximizing a window, the window extends up by a few pixels more than any other maximized window. Now, normally this wouldn't be a problem as the top of the screen would cut off any extra padding. However, using a program that reserves the screen edge shows that a maximized Firefox window indeed extends past the regular window border by exactly 8 pixels. What's more, when using Windows Snap on two separate Firefox windows, one of the windows respects the screen edge while the other does not! This leads to the window control buttons at the top right of both windows to be in different vertical positions, which is difficult to use. No other programs I have exhibit this behavior, which is why I'm turning to Mozilla support. I don't know if the issue has to do with the browser or how Windows 10 renders the desktop, but it throws off the design of the desktop as I intend to display it. In the provided example picture, the left window demonstrates predicted behavior where the upper border of the window is at the position I intend (40 pixels from the true screen edge), while the right window can be seen extending past the left one by exactly 8 pixels. I have tried this with extensions disabled, in safe mode, and every other way I can think of and the problem persists. No other programs exhibit this issue. This is utterly baffling to me and I hope someone might understand and be able to suggest any solutions. Thank you!