@thelovebug@s.wefamlee.be I scrolled through the list of issues for #postActiv and found this about full acct URI mentioning for local IDs:
https://git.postactiv.com/postActiv/postActiv/issues/90
As a matter of fact, it works great in !GNUsocial (at least in the nightly branch, which is the one I probably recommend for everyone and will "soon" merge into master). It gets shortened automagically, so visually this is a bad example, but here I wrote the full .@anotheruser@social.umeahackerspace.se: @anotheruser
cc: @maiyannah