Blue rectangles on selection disappear after pressing Delete key

[grofaty]

Pinta 1.7.0.194 on Ubuntu 14.04.

1. Rectangle Select and draw selection.
2. Press Delete key to delete selection area.
3. After key was pressed the small blue rectangles at the edges of selection just disappear. It looks (because of no blue rectangles at edges) like no resize of selection is possible. But if you move mouse to the edge of the selection (anyone you like) the selection is still possible. I expect that blue rectangles after pressing Delete key should not disappear.