In past versions when I clicked on an email address in Foxfire, I was taken to my Thunderbird email program. Since I downloaded 4.0 I get a pop up box trying to take me to Outlook, which I don't use. How do I get it to send me to Thunderbird again?

I'm no longer able to click on email addresses in Foxfire and get transferred to Thunderbird (the email program I use). This is a change from past Foxfire versions, where it worked just fine. You spoiled me, now I want the same ease of use. How can I fix this?

Thanks!