Set mailto: in Firefox and Bluefin
1. Configure Firefox (Internal Handler)
This tells Firefox to open Gmail whenever it detects a mailto: link.
Open Settings: Click the menu button (≡) and select Settings.
Find Applications: In the General panel, scroll to the Applications section.
Update Mailto:
Find mailto in the Content Type column.
Click the Action dropdown and select Use Gmail.
Manual Trigger (Optional): If Gmail isn't in the list, open Gmail and look for the Double Diamond icon in the address bar to "Allow" it, or use the javascript:navigator.registerProtocolHandler(...) command in the console.
2. Configure Bluefin (System Handler)
This tells the OS to send "Share" requests from other apps (like your file manager) to Firefox.
Open GNOME Settings: Open the Activities overview and type Settings.
Set Default App:
Navigate to Apps > Default Apps.
Click the dropdown next to Mail and select Firefox.
Terminal Override: If Firefox doesn't appear in the dropdown, run this command:
bash
xdg-settings set default-url-scheme-handler mailto firefox.desktop
Use code with caution.
3. Workflow Limitation
Opening: Clicking any email link now opens a Gmail "Compose" tab in Firefox.
Attachments: Because of browser sandboxing, sharing a file from your system will open the compose window but cannot attach the file automatically. You must drag and drop the file from your folder into the Gmail window manually.