Going back to 13.0.2

It's not worth wasting time on 13.1, when it takes many seconds just to flag an image or when you leave the mask tool and it takes 10 seconds just for the show overlay red to go away you know they spent all their time on "cool" stuff and still don't know how to do QA, or product design. Save yourself the trouble and wait on this update. 

By @JCRBphoto

Maybe it was just a typo, but as of today it’s at 13.3, not 13.1. A number of performance improvements were noted in the release notes. In fact, this particular 13.3 release seems to contain a lot more “invisible” under-the-hood tuning, relative to the few new features that were added. For example, the internal engine for sync was modernized and replaced, and it looks like the preview architecture was redone.

The release notes also say there were Develop improvements, which is the module where you were seeing problems.