If I try to scroll on the computerscreen, the coordinates are a bit offset.

In window-mode:
Top-left corner: x=11 y=5
Bottom-right corner: x=51 y=19

The coordinates are even different, if I use minecraft in fullscreen or window-mode.

Minecraft version: 1.14.4
CC-Tweaked version: 1.14.4-1.86.0
My forge version: 28.1.102