@ davescm, I appreciate that you're trying to help, but I've been reporting problems to Adobe for the last ten years when the infamous - and still not fixed - brush tool lag started. Every single Mac I've used and owned since High Sierra has been the same story with photoshop. Lag, glitches, slowdown, unpredictability. Take your pick of any Mac and OS combo and Photoshop has been misrerable on it. There has been a cycle of Adobe blaming Wacom, Adobe blaming Apple, and nothing being resolved. Photoshop's performance is worse than ever even on high-end hardware. I don't know what the common link is. We've tried to figure it out for nearly a decade. Right now photoshop is near unusable for professional work for a large percentage of its userbase. And Adobe won't listen to us or help us.
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