I'm browsing from behind a Firewall using this weird proxy server, which essentially acts like a man-in-the-middle and switches up the SSL certificate of the server with its own. So the certificates regard the site I'm after, but are supposedly issued by "FooBar inc." (that's the organization I'm in).
This means that essentially every single page which FF tries to get - it believes it encounters an error, about how the sufficient type in not set, and I get:
Warning: Potential Security Issue Ahead
etc. etc.
SECURITY_ERROR_UNKNOWN_ISSUER
I tried exporting the certificate and importing it, as suggested here - but this didn't work. Trying to import the .crt I got a message saying that this was not a valid issuer.
What can I do?
Note: I'm using CentOS 8.