You mean so long as everyone standardizes around a non-standard, rather than the actual specifications of the standard, it'll work?

I think I prefer just adhering to the standard in the first place.

That's what "strict in what you issue" means

If you are always going to blame the issuer for not being strict... what's the point of the accepter being liberal?

I agree that the issuer should always be strict; and if accepters were strict too, then buggy issuers would be detected immediately and never make it into production. Instead they make it into production, where they will sometimes work and sometimes not, depending on the accepter stack in use at the time and context and how the accepter stack chooses to interpret 'liberal'.

It locks you into the particular "liberal" implementation you started with, or at least significantly increases the risk of changing implementations.

"liberal" by definition here means _beyond the spec_, according to no spec. So different implementations may have different varieties or extents of 'liberalness,' and switching implemenentations will almost necessarily give you a different set of acceptable requests. If they were all the same, that'd be adhering to some spec, not being liberal in your acceptence of it.

"Liberal acceptance" may or may not have ended -- we don't really know if Cowboy accepts only exactly what is legal according to spec or not -- but the bounds of what is liberally accepted defintely changed. As it neccesarily will any time you switch implementations, since 'liberal' is by definition not according to any spec.