This seems to be something that’s happened in the last build or two, but i find that when i’m dragging a curve and want to make a copy of it, tapping Alt/Option briefly shows the [+] icon next to the cursor, but it disappears and the copy-while-dragging doesn’t happen.
This is also a longstanding problem on the Windows side - sometimes you have to tap Alt repeatedly to get the “+” to show up. Nobody has ever been able to explain why to my knowledge. Related to the fact that Alt also suspends Osnaps as well, probably a question of signal timing…
I’m also getting this problem- far more often than in the windows version. Would be great if it could be sorted