One of the other noticeable differences is the improved support for Bootstrap 5, using
adp:icon
as presented at the OpenACS conference. These generic icons are used intensively on the main packages to provide a consistent appearance.
Many of the (site-wide) admin pages were overworked to provide a more modern look-and-feel. See a few examples below.
acs-admin/subsites
https://localhost:8443/acs-admin/apm/package-instances?package_key=xowiki
admin/site-map