Physics collision boxes not saving after edits

I'm having an issue where no matter what I seem to do, any changes I make to the physics collision box don't get saved. My player sprite is a 120px by 120px square, but the physics fixture (if I'm using that term right) is offset by one pixel. It's size was also causing unwanted issues, so I wanted to shrink it a little. But any time I go into the "Modify Collision Shape" menu of the object, no changes I make get saved. I had this same issue when initially setting it up a while ago, but at...

Physics collision boxes not saving after edits