Created attachment 108781 [details] Zoomed In Image of the Missalignment If you notice in this image, I am barely touching the border of the window and then the cursor changes to the stretch cursor. Notice how the cursor is not in the center aligned with the window border, so you get the impression that you are not touching the window border to stretch it but you are touching something else.
I think this is intentional? Otherwise it's really hard to position your cursor precisely enough to hit the small target. People without precise mousing skills (new users, children, the elderly, people with issues that make their hands shake, etc) would find it very hard to do.
Or is this only observed with the mouse KCM?
I think that makes sense, so it would at the same time change back to pointer at the same level when the cursor exits the area. I hope that makes sense. I think right now it changes back to regular pointer too early.
I think what's going on here is that you have big borders set in System Preferences > Application Style > Window Decorations > Border size. If you reduce the border size, then you'll see a smaller zone of resizability. I like "No Borders", myself.