cannot compose emails with mail to links because Firefox interferes


I used to be able to open a new email with to, from, etc. fields showing whenever I clicked on a mail to link within an email I was reading. But somehow Firefox not only seems to think it's my default browser, but it also opens up the browser when I click on mail to links. Using Gmail, win 7 and the newest versions of jaws. How can I get back the edit fields to write an email using mail to links within an email?