One thing I’m trying to keep an eye on is sup. Not much information at all besides a snippet of 1 to 1 encrypted messaging for activitypub, but the tidbit of working with any fediverse account is interesting. Potentially that could help deal with the different fediverse implementations of messaging. Of course, like I said, this is just me making up assumptions, it could not work the way I envision it at all. The creator just posted something 5d ago about it with “soon” though, so I’m hoping to read more about it