I mean, these ain't like in the old days where a few Megabytes got you #Pidgin and other Multi-Protocol Clients of the old days where everyone had to implement bespoke, custom and incompatible and *often completely undocumented, proprietary * protocols like #ICQ, #AIM, #SIPE, etc.
- Nowadays all these do have some kind of #WebApp or Web Interface one can just login (because *none of them do proper #E2EE with #SelfCustody of all the keys!) so this should be way easier these days: All they do is do HTTP(S) GET/POST so the most critical part is to attain credentials like a #Login #cookie and to basically run a console on i.e. #Firefox to reverse-engineer the #API...