During your upgrade, do you recall using Firefox's Refresh feature? This can happen when Firefox starts up slowly and says in order to make it less sluggish you can refresh/restore the browser. The best indication is that an Old Firefox Data folder appears on your desktop.

If so, your Firefox may no longer be set up to work with your security software. Some programs such as Kaspersky, ESET, avast 2015, and Bitdefender will filter your web traffic for threats. In order to filter secure sites, they must present a "fake" certificate for the site to Firefox, so they can be "in the middle" and read your secure communications. When you use the Refresh feature, then Firefox no longer is set up to trust the fake certificates.

Does that sound like a possibility?

Yes that i did a refresh recently but i didn't have this issue show up until i upgraded. What would be the solution if it is that?

It depends. Do you use one of those security programs that may be presenting fake certificates to Firefox? I'm not sure what browser you're using at the moment, but if you're on Facebook in that other browser and you click the padlock icon in the address bar and look at the details, does the Issuer/Issued by section match up with your security software vendor?

Yeah i have avast 2015. And that is what is showing as the certificate

You can disable HTTPS scanning in Avast Web Shield.

• [/questions/1032509#answer-657191]

Did you just update to Firefox 37? It has an issue and upgrades have been suspended.

Install an older version of Firefox {web link}

Hi FredMcD, I think only users with startup crashes are affected by the issue you're thinking of.