See attached screenshot.

Before 1.9.6.0, the default was set to highlight 'OK'.

When tapping the Enter key on the keyboard, the 'Cancel' is selected and nothing happens. As a versioning program, no change is permanent so I don't know why 'Cancel' should be the default action. As programmers, we do not use the mouse to click OK in the pop up, we want to press enter after selecting an action that we WANT to do.