This could have changed, but must have been quite a while ago, if so. How did it use to work? And how would you want it to work?

option+left arrow moves cursor to a word left, so I’d expect option+shift+left arrow to move the cursor to a word left and select everything between current cursor’s position and the new position(same as the way it behaves if it’s not a comment). I can’t recall if/when it used to work though, I just noticed it today and wondered if there are any changes around that in recent versions

On Mac option+left moves cursor to the left of the form/sexp. And with shift added, it selects. But it shouldn't be bound to a Calva command when the cursor is in comments. Maybe we have a regression. Please file an issue.

here’s the issue - https://github.com/BetterThanTomorrow/calva/issues/1961 let me know if more details need to be added

Yeah. Ctrl+Shift-Left/Right (Linux) are totally broken for comments. Depending on some unclear factor, it either will not move the cursor at all, or will select from the cursor to the beginning/end of the next form found outside of the comment block. Both behaviors are definitely neither expected nor desirable.

I think the context for cursorInComment must be broken somehow. No idea when that happened.