Hey there - just installed 2.90 - I tried to change one of the snapshots in a preset. Helix would not select - showing a yellow warning message in HX edit. I had this problem in an earlier version already - the solution was to to save the preset while the error message in HX Edit was shown. This actually worked in this case also - but only after the machine had a total freeze twice! So maybe be a little careful and check all your presets before your next (online)-Gig.
Also the copy/paste function by touch-holding the buttons for snapshots does not work !
All the best Alex