I'd like it be possible be able to single click an item's envelope and have all the points deselected. I have tried many combinations of settings to allow for this, but it seems that envelope lane modifiers are treated differently to item envelopes, and there's no way to be able to actually set this up for item automation. I have a thread here that has determined this to be the case: https://forums.cockos.com/showthread.php?p=1865639
In every DAW I've ever used, clicking anywhere outside of an envelope point deselects all envelope points. This is how I would set it up if there was an action instead of a mouse modifier reset to allow for this:
but this will only work once.