I think it may be nice to either have hotkeys or modifier clicks on the arrows to fold all levels beneath current, unfold all levels beneath current, fold all levels except those between current and its currently most unfolded sub-level, fold all except current, unfold all levels to the depth of current, etc…
I am sure there are some other good ones I don’t have here. Personally, I like modifier clicks on arrows. For example alt-click arrow may be good for fold all except this level. Ctrl-click arrow feels like unfold sub-levels could work. Some of the other more nuanced ones may benefit from hotkeys.
If this is already a topic, I apologize. I promise I did do a few searches. Thanks for everything.
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