not so easy....
I know of no preference to do this for ALL Groups.
I don't even know HOW you would do this if you wanted to....
The only similar function i know is Option-Clicking on a Group disclosure triangle opens all Groups and nested layers in that particular Group.
Maybe some setting with you mouse that has option enabled??? Wild guess that one.
Frustrated this morning, I did check my mouse, and you are correct... it was enabled for option clicking (like two right clicking buttons). Which is a good prank... if you ever want to ruin someones day...
Editor/Chess Player, Washington DC
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