SSL_ERROR_UNSUPPORTED_VERSION problem to loading
SSL_ERROR_UNSUPPORTED_VERSION show interface
I think that this can happen if there is a mismatch between the TLS protocol the server supports and the TLS protocol your browser supports. Using a proxy can also cause this, but is also possible that the server doesn't support modern TLS versions (TLS 2 and 3).
Make sure that these prefs are default on the about:config page.
- security.tls.version.max (4)
- security.tls.version.min (3)