adp:icons can be used on ADP pages with
<adp:icon name="NAME" title="..." style="..." class="...">
The last three arguments are optional. Bootstrap Icons defines in version 1.8.1 more than 1,600 icons. When installing Bootstrap Icons, all of these are usable independent of the style of the site.
However, when one wants to keep e.g. some subsites in Bootstrap 3 and others in Bootstrap 5, and the classic Bootstrap 3 look-and-feel should be kept, and the identical markup should adapt its Look-and-Feel depending on the subsite theme, there are some restrictions. OpenACS supports the icon sets "classic" (old-style gif/png images), "glyphicons" (Part of Bootstrap 3) , and the "fa-icons" (usable for all themes). Some of the icon names are usable for all OpenACS icon sets, some of these can be used without further mapping as replacement of the gyphicons of Bootstrap 3.
See below for lists of valid names.
Currently defined generic adp:icons, working with icon sets "classic", "glyphicons", and "fa-icons". This means that via switching the themes, different icon sets are used without the need of rewriting any code.