How to update server certificates

[Cixert]

I would like to know how to update server certificates on any browser. Especially on Firefox.
Microsoft has update packages with certificates but these are already obsolete.

-The certificates that are installed automatically after visiting a web page after clicking on "get certified", are only for that web page?
- Is it necessary to install or update the certificates of the various certification authorities "one by one" or is there a procedure to update all at the same time?
- Is it possible to implement TLS 1.3 on Firefox 12?