That’s to add an “authority”. Done that. But firefox doesn’t find a personal (id) cert signed by that CA (fnmt.es)

I can’t. Firefox on Android doesn’t handle my personal certificate so it’s a hassle to access gov sites

I don’t see the date of the offer, but they’re in the (bad) news these days

https://www.bleepingcomputer.com/news/security/internet-archive-hacked-data-breach-impacts-31-million-users/

File existing and we’re able to read it are two quite different conditions