This sounds like texinfo (invoke via the ‘info’ command). Fun fact ironically a lot of the original groff documentation is written in texinfo, see: https://list

This sounds like texinfo (invoke via the ‘info’ command). Fun fact ironically a lot of the original groff documentation is written in texinfo, see: https://lists.gnu.org/archive/html/groff/2005-10/msg00107.html https://lists.gnu.org/archive/html/groff/2005-10/msg00107.ht...