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 13 hours ago by Nomen