Just wanted to note that I've been seeing some strange animation problems with TS transitions on Sierra 10.12.4 Beta (16E154a). Some transitions like Reveal work once or twice, then completely stop working thereafter. Other transitions, like Cube or Slide, seem to work ok, but there is a noticeable black flicker in between each space transition. These issues just popped up with the latest Sierra update. If it would it help, I could try to get a screen capture to show the problems.