It sounds like Firefox is using two different profiles: your regular and then the one that opens when you click a link. Open Firefox like normal and go to the <code>about:support</code> page in Firefox by typing that in the Firefox address bar. In the '''Application Basics''' table, make note of what's listed in the '''Profile Folder''' row, specifically the last part of it. Now close Firefox and open a link in your email. Go to the <code>about:profiles</code> page. You will probably see multiple profiles listed there. One of these listed profiles should match the last part of what was listed in the '''Profile Folder''' row in the previous step. If none of the profile names match, a exact copy of what was in that row should be in the '''Root Directory''' row of one of the tables on the About Profiles page. Once you've found the profile that matches, you should see a '''Set as Default Profile''' button under the table for that profile. Click that button. Then close Firefox and now Firefox should open normally whether you click a link in your email or you open it another way. More information about what I've described can be found in the [[Recover user data missing after Firefox update]] page, although the page title doesn't quite match the issue that you are having here. Hope this helps.