Selection cursor does not appear consistently when around edge of table

[velara3]

The code for changing the cursor when around the edge of the table has been added but it is inconsistent. It appears sometimes when moving the mouse down but not up or the other way around. It seems the mouse move and mouse over events may not be dispatched consistently. I've added trace statements to both and mouse move does not seem to fire every mouse move (maybe because I'm canceling some mouse events) but mouse move is inconsistent as well. It may also be that the setMouseCursor is being called from another place and that is changing the cursor back to an ibeam.

Steps to reproduce

1. Open TableExplorer
2. Click Add Editable table
3. Move the mouse around the left and top edges of the table
4. Move the mouse from top to bottom and bottom to top on the left and top edges

Expect result
The cursor to remain one of the 3 selection cursors

Actual results
The cursor is inconsistent. It works sometimes or when the mouse enters from a certain direction such as top to bottom but not the other way around.