Saving as Tiff

The Save As dialog now only shows formats that support all the current properties of the file.

This was done to circumvent a policy change in MacOS Catalina. Since Apple didn't want to change it, Adobe had to find a way to work around it.

So Save A Copy was added as that workaround. It lets you directly save to all other formats, while leaving the original.

Actually, this reverts to how Photoshop originally worked - only then you didn't even have Save A Copy. If you, for instance, wanted to save a layered file as jpeg, you simply couldn't, there was no way - for the simple reason it's not allowed in the jpeg specification. You had to get rid of all the offending properties before you could save.

The ability to directly save a jpeg-copy-on-the-fly was introduced sometime around CS4. But with Catalina, that function didn't work properly anymore (as evidenced by about a million threads over the last year or so), hence this necessary change.