When I click an email link directly, or by right clicking and selecting open in browser nothing happens. When I click an attachment it has me choose an application, then will not open it. In all emails. I have told it to save what application to open with. Firefox is the default browser. I tried safe mode. Nothing in this link works https://support.mozilla.org/en-US/kb/Hyperlinks-in-Messages-Not-Working . This is on Linux Gnome.