there seems to be issues with the player coordinate tracker and the block coordinate tracker. it seems that "XYZ" and "Looking at" are usually a block off or more, its only affecting the x and z but its a big issue. i have created multiple test environments, i tried playing offline with a world from pre3 and one from pre4, and tried playing from multiplayer. the problem still persists and each world the coordinates are off by 1 - 2 blocks. the included screenshot is an example of the issue.
There is no -0, see MC-4794