These are just screen orientations that have been set previously.
They won't be used (or snapped to) if you have it set to 0° as in your image.
I don't know of any way to delete these unwanted angles from the list.
If elements are snapping to odd angles when your screen orientation is 0°, then you will want to look at the rotated grid settings.
You may be using a slightly rotated grid rather than the square one.
Barry.
One of the forum moderators.
Versions 6.5 to 27
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