Multi object editing - transform snapping.
The snap bug exists in 2.79b. The bug isn't a major problem and shows itself as the selection snapping to a non existent uv. If the user doesn't like the new position of the selected uvs then they can keep moving the mouse to get a better position.
The bug is caused because the selected uvs can snap to themselves. It's a two stage process, first the selected uvs snap to a 'legitamate' uv, then they snap to the new position of one of the selected uv's.
I'll make a bug report when reporting is allowed.
- There are two uv unwrapped objects.
- You're in uv eding mode with two objects selected. Each object has one UV vertex selected.
- 'Snap during transform' is on, 'UV element to snap' to is set to vertex.
Press 'G' to move the selected UV vertices.
Before the patch - the vertices only snap to one object.
After the patch - the vertices can snap to both objects.