Firefox root certs or cert authorities and XP

[Nomen]

I've just fired up an old XP PC and have updated the windows root and intermediate certificates but my question is - how does firefox interact with these certs?

The PC has FF 39.0 and is throwing up cert errors when I bring up some sites.  Does FF use these windows certs, or does it have it's own store? 

If it has it's own store, is it built into the distribution image when you install it?  Can you have FF just update it's own certs without having to update FF itself?

Are there cert update packages for FF?  Or will it take the windows cert files?

(On my win-98 pc at work, running that modded version of FF2, I never have cert issues and I throw a lot of sites at FF, usually have to view them with no style, but they still come up)

 

 

Edited December 23, 2025 by Nomen

[ED_Sln]

Perhaps the issue is that FF 39 does not support TLS 1.3, so websites that use this protocol cannot be opened. FF 2 has an encryption engine update, so websites with TLS 1.3 can be opened there.

To enable the browser to use system certificates, find (or create) the security.enterprise_roots.enabled parameter in about:config and set it to true.

Edited December 25, 2025 by ED_Sln