SAML SSO for Mozilla via Github failing with bad /authn_response

[jryans]

Transferred from @ara4n's element-hq/element-web#12801:

Hope this is the right place to say this: I tried to signup using github but after the authorization was done, redirected to mozilla.modular.im and the webpage was like:

Method Not Allowed Your browser approached me (at /_matrix/saml2/authn_response) with the method "GET". I only allow the method HEAD here.

Convo is here: https://matrix.to/#/!pcfWjiETvnVuspPLPl:mozilla.org/$IO71OeAO1JOD9WeTOiTZ5_uOJahvRyO840AoWfip9Dg?via=mozilla.org&via=matrix.org&via=maunium.net

[richvdh]

I believe this is fixed by matrix-org/synapse#7058.

[babolivier]

I believe this is fixed by matrix-org/synapse#7058.

Yep, and it's been released in v1.12.0 (so should soon be deployed) therefore I'm closing this issue.