The adp:icon can be used as followed:
<adp:icon name="NAME" title="..." style="..." class="..." iconset='...' invisible='...'>
The current version of OpenACS supports the 4 icon sets "classic" (old-style gif/png images), "glyphicons" (Part of Bootstrap 3), "bootstrap-icons" (usable for all themes), and "fa-icons" (usable for all themes).
The generic icon names can be used for all icon sets, since for these, a mapping from the specific icon set to the generic name exists. When using adp:icon with a generic name, the themes/iconset causes different icons to be used, without requiring you to rewrite any markup.
In the listing below, the glyphicons are only rendered when running under the bootstrap3 theme. The current default icon set is @default_iconset@.
@genericHTML;noquote@