https://spec.matrix.org/latest/

https://spec.matrix.org/latest/client-server-api/
https://spec.matrix.org/latest/client-server-api/#get_matrixclientversions
    ! GET /_matrix/client/versions
    Rate-limited            : No
    Requires authentication : No
    https://spec.matrix.org/latest/#specification-versions
https://spec.matrix.org/latest/client-server-api/#client-authentication

https://spec.matrix.org/v1.2/client-server-api/
https://spec.matrix.org/v1.1/client-server-api/

https://matrix.org/docs/guides/client-server-api
https://matrix.org/docs/api/client-server/#!/Room32participation/sendMessage

@goncharenkoii:matrix.org
identity server: vector.im

/_matrix/client/versions
https://organicdesign.nz/Matrix
# CORS Issues

https://gist.github.com/RickCogley/69f430d4418ae5498e8febab44d241c9

https://webapps.stackexchange.com/questions/131056/how-to-get-an-access-token-for-element-riot-matrix