For example, while asciidoctor supports the kbd:[F1] macro and we do the proper rendering in this back-end, since reveal.js doesn't have the CSS for that feature, the kbd macro does nothing on the visual output.

There are several things unsupported. Let's track them here:

• kbd macro (related Replaced <kbd> element with <span> for the keyboard sequence. #76, kbd macro doesn't work #276)
• tables (Table frame options and compact tables #56, Vertical table alignment not working with reveal.js backend #42, Tables do not listen to "grid" and "frames" options #29, Table not generated correctly when one column contain bullet list #23)
• quotes
• source code call-outs (Font icons for source code callouts #54)
• .unstyled role to create lists without bullets