I've been using Photoshop extensively for 15 years on a PC. I just upgraded to a new iMac and got Photoshtop CC 2015.
I'm used to double clicking a layer to change the layer name, but on the mac with CC 2015, usually if I do that all I get is the name “greyed out” and I can’t do anything to it. The History tab adds a state that says “Color Change” which I don’t even know what that means! I have to click a THIRD time to get the layer name to become blue, and therefore editable.
This isn’t always the case, sometimes a double click will work, layer becomes blue and I can rename it. It seems so random! I’ve never seen this before