P: Arrow keys no longer advance to next photo in filmstrip in Develop

When I use "+" key to go up on the exposure slider it stops my arrow keys from being able to move left and right on the film strip. If I press "+" it does its job and makes the slider go up but it makes it so I can't go left and right using the film strip. However, if I press "-" it works fine and I can still select the next and previous images with the arrow keys.

I've gone back to 13.4 and it works fine so it's clearly the update is the problem.