Blocks annoying video ads on YouTube, Facebook ads, banners and much more.
Adblock Plus blocks all annoying ads, and supports websites by not blocking unobtrusive ads by default (configurable).
Organize your schedule and life's important events in a calendar that's fully integrated with your Thunderbird email. Manage multiple calendars, create your daily to do list, invite friends to events, and subscribe to public calendars.
Did your friend send you a cool link? Want to read the rest of that interesting article? Don't want to open up your web browser just to view it? You don't have to! Just view it in Thunderbird with ThunderBrowse!
Czech spell checking dictionary for all Mozilla applications includes both standard and ascii version.
Minimizes Mozilla windows into the system tray. Also includes a right clickable tray icon menu to further load only the windows you want visible...
Note from Mozilla: This add-on has been discontinued. Try Add-on Update Checker instead.
Notifies you when updates are available for your extensions and themes.