How to remove fake certificate in browser and mail client?
 

I didn't pay attention and accepted certificate of the fake site. Now I understand this, but how to remove this certificate? So I will be warned when open fake site again?

Re: How to remove fake certificate in browser and mail client?
 

Look into /home/user/.mozilla/microb/cert* files.
If you see that site in cert_override.txt - try to remove it (save it before!)
or remove both and visit a site again.

EDIT: don't forget to reboot after that.