Same issue here. My Firefox on Fedora gives "SSL_ERROR_UNSUPPORTED_SIGNATURE_ALGORITHM".
I found a bug report[0] which suggest it is (mostly) a server issue. Fedora refuses to use SHA1, and the server ignores the client's attempt to negotiate a more secure algorithm.
I found a bug report[0] which suggest it is (mostly) a server issue. Fedora refuses to use SHA1, and the server ignores the client's attempt to negotiate a more secure algorithm.
[0]: https://bugzilla.mozilla.org/show_bug.cgi?id=1749670