The little resize symbol mostly just indicates that the window is resizable. You can resize it from both corners (and both sides, and the bottom too!).My biggest issue with the window resizing (I’m not sure if it’s fixed on the latest beta) is it always seems to put the resize handle on the wrong corner. If I have a tall narrow window docked to the left of the screen, it puts the resize handle on the bottom left corner which means all I can do is make it narrower. Surely users might also want to make windows wider and therefore it would make much more sense to allow resizing from the right corner (or just let us use both corners!).