I find this so frustrating whenever I want to resize a window by grabbing its border. I have to be very accurate, the border seems to be only 1 pixel in thickness. Windows is more forgiving.
Also, the cursors that show the resizing are bad. They indicate that you always want to enlarge the window, which is not always the case. And the fact that majority of the resize cursor appears not in the dead center of the mouse cursor but are offset somewhat makes it more clumsy.
Where does the Linux community find its user interface guys? Seriously.
Anyway, not here to bash about everything, just the things I find so wrong that are so trivial to fix.