Try going to settings > Privacy and settings > Manage Exceptions under "Enhanced Tracking Protection" then add the website which uses trusted certificates to connect. Hope this solved your problem. Have a great day!

I cannot see from where i can add the website could you please help me with that?

Hello,

I work in IT and i use Firefox developer edition to work on website issues, in the past i would be able to just accept the self-signed certificate and continue to the website, but after the most recent update i lost the ability to do this. Is it not possible to regain this function? I understand the security behind it but i have a firefox profile setup specifically for work. All i'm looking is for a pratical solution because as of this moment i have to use Edge to check on websites.