To login to Plesk control page in Firefox please use the following steps:-
1) Enter your domain name in the Firefox web browser.The control panel works on
port 8443 with https so you need to enter the URL like this :-
https://your_domain_name.com:8443
(Replace your_domain_name with your domain name)
2) You will get the warning Page saying "The connection is Untrusted" Click on "Add expection".
3) A certificate page will be pop up on your screen.Click on "Confirm Security Exceptions".
4) Once you confirm the "Security Exception" the "Plesk login page" will be opened
on your Firefox web browser.
