Hello,
After updating to Photoshop 21.2.0 (June 2020 release), on a Mac, running 10.14.6, I've encountered a bug toggling between a layer mask and its layer using keyboard shortcuts (Command + \ and Command + ~).
After clicking CMD + \ , I am taken to the layer mask, as per usual, but, now it also goes into overlay mode. I have to click \ to get out of overlay mode.
This happens on all three Macs, I've used, all on 10.14.6.
Thanks, in advance, for checking into this.