We have the same problem in our installation too.
I cannot tell if it has been there before the upgrade to zammad 6.2 last friday, as we had the group selection hidden via core-workflow in our customer web form till yesterday.
Logged in as agent or administrator all groups are visible and selectable.
It doesn’t matter which browser we use (Chrome, Chromium, Firefox, Edge, Vivaldi) and if I delete cookies and browser cache.
Shouldn’t we open a issue in github for this problem (haven’t had a look today if one already exists) ?
EDIT: I forgot to mention, that we filtered the groups for ticket creation, but the removal of this filter doesn’t matter (Channels => Web => Group selection for Ticket creation). Customers cannot see the group names in the dropdown menu.
Best regards and thanks in advance
Peter