This is available in the DopeSheet, GraphEditor, and NLA Editor.
Currently:
- Dopesheet advertises to take selection into account...
- ...but doesnt - which might be a mistake in rBe3842d1ca4dd
- Graph Editor does not mention selection...
- ...and also does not take it into account
- NLA does not mention selection...
- ...but takes it into account
Now:
- make them all take selection into account (you can still do a quick 'Select All' prior to get the full range -- better than not being able to set this based on selection)
- mention this for all in the tooltip.
- also reword to 'Set Preview Range to Selected' since using the term 'Auto' impilies this would change on selection change.