In version 2.9.2, when you focus the X or Y field in the Select Tables interface for modifying PDF pages, it also selects the checkbox for Delete. This is 100% not useful as it requires you to deselect the checkbox before clicking the GO button. If you are editing X or Y, it's pretty safe to say that you are not interested in deleting the table in question.
This is clearly bug, moving to bug tracker.
This bug was fixed in repository and will be part of a future release; thanks for reporting.