After upgrading to OS 10.13.xx XP.11.xx (I have the latest of both) I'm seeing constant fluctuations, from 10± to 30± FPS (a few seconds low and then a few seconds high and then back down again). I have tried running XP without any other startup programs running, just XP and the OS, but to no avail. I've not been able to enjoy my favorite hobby for a couple weeks, with no joy in sight.
I have read that others are seeing this behavior, and that LR has filed a report with Apple.
What is the status?