Stefan Breunig
9f2765e97b
Steps to reproduce this particular issue: 1. draw a box 2. select the box 3. hover over one of the corners as if you want to resize the box (no click needed) 4. press DEL to delete the box 5. left click on the canvas Note there are two more destructive operations on the canvas' `shape` in `undo_last_line` and `reset_all_lines`, but former is dead code and latter I don't know how to trigger. Thus I can't be sure un-highlighting will not lead to visual glitches. There are other potential fixes, e.g. checking in `selected_vertex`. I can rework the patch, but then again, the fix is so straight forward that telling me is probably more effort than just rewriting it. See #750 See #605