Currently you can use a Font Awesome icon in buttons throughout AIM.

Fontawesome allows for composite icons using layers to generate new icons

Which is just
<span class="fa-stack ">
<i class="fal fa-globe-stand fa-2x"></i>
<i class="fal fa-slash fa-stack-2x" ></i>
</span>
AIM is just taking the part inside the <I class='"> marks.
Could it be possible to modify the field to show the full css class so that it can be expanded to the above as this would allow for more versatile icon use.