My masked images are not displaying correctly in RGB. When I convert to cmyk all is fine. The mask thumbnail displays correctly in the layers panel but not on the actual image. The image is fine as in if I save it and place into Indesign the masking is correct, but this problem is obviously making mask refinement impossible working in RGB. I have hobbled along with this problem for a while – it started with Photoshop 2019 but I could get round this by working in v2018 when required. Since upgrading to Catalina though my 2018 version won't launch. Currently using Photoshop 2021. Is this a hardware / graphics issue, or software. Screenshots attached of problems and my hardware set up (2014 imac – works absolutely perfectly for everything else). Hope someone can help!.
To verify if it might be a GPU-driver-issue try turning off »Use Graphics Processor« in the Performance Preferences (Photoshop > Preferences > Performance > Graphic Processor Settings) and restarting Photoshop – does it have any bearing on the issue?