true, it also happens to me very often.. that TSF people just do /multiversion on without thinking what version the level is. really annoying, yes. but that mistake belongs to the people hosting, not to jj2+ where the purpose is you can join more and different servers than normal. still, would jj2+ be able to recognize the level (.j2l) version, if the server is TSF and you are running 1.23? if so, try to make these fields 'unable to join (grey)' instead of 'being able to join (white).'