SP ACS extra query string parameter rejected by IdPv3, not rejected by IdPv2

[Tom Zeller]

> Not exactly sure, but it looks like the V2 AuthnResponseEndpointSelector checks the ACSURL index then the location, while the V3 DefaultEndpointResolver checks the location then the index.

Well, I believe the above is incorrect. V2 only checks the index, while V3 checks both the index and the location. So, V2 will ignore an incorrect location if the index matches.