Reviving an old General Semantics proposal: borrowing from scientific notation and using subscripts like 'Gwern2020' for denoting sources (like citation, timing, or medium) might be a useful trick for clearer writing, compared to omitting such information or using standard cumbersome circumlocutions.
Moved to gwern.net
Agreed.
Agreed so far…
You'll need a bunch in a single passage. If you don't need to disambiguate a large hairball of differently-timed people (like in My Best and Worst Mistake), then you probably shouldn't bother in general. Put another way, you're going to want to have a dense, if localized, cluster of people-times that need disambiguating for this to be a better idea than using parentheticals.
I'm struggling to see how this is an improvement over "on FB" or "on Facebook" for either the reader or the writer, assuming you don't want to bury-but-still-mention the medium/audience.
Not without context or some other way to reduce the universe of things "FB" might refer to. "My wife complained on FB" is probably enough of a determiner most of the time for most people (unless I'm really underslept), but an "FB" subscript isn't immediately obvious to people who aren't used to that sort of thing.