This is happening for me, and gets resolved when I disable the GPU, which is of course not at all preferred.   My system: MacBook Pro 16-inch 2019, AMD Radeon Pro 5500M 8GB, Lightroom Classic 14.0.1   Graphic Processor on (auto):   Graphic Processor off:   ... View more

"iMac (Retina 5K, 27-inch, Late 2015) Graphics AMD Radeon R9 M395 2 GB"   That graphics processor is no longer supported by AMD, with no ongoing bug fixes to its driver: https://www.amd.com/en/support/graphics/amd-radeon-r9-series/amd-radeon-r9-300-series/amd-radeon-r9-m395   LR's AI commands are very sensitive to bugs in graphics drivers, and Adobe is constantly changing the code in LR and Camera Raw that uses the graphics processor, trying to improve performance. It's very possible that the changed code in LR 13 is tripping over bugs in the old driver for your graphics processor. There are other reports here, starting with LR 12.4, of LR's AI commands no longer working on old Macs with AMD GPUs.   You could try disabling LR's use of the graphics processor for AI commands by following the steps here: https://helpx.adobe.com/camera-raw/kb/acr-gpu-faq.html#lens-blur   ... View more

Thank you for the recommendation.  I will try that.  Sorry I did not see your post earlier. ... View more

Simple answer is dont buy in to Apple's repungent OS's .  every time they change something they break something.. As much as i hate Gates and his merry men , windows atleast does not require you to buy new software everytime they update Windows.   ... View more