Foobar Controls Requires Restart
Allows you to control the Foobar2000 Mp3 player from the Firefox window...
ConQuery Requires Restart
Context searching for everyone and URL manipulation tool for advanced users...
As of Firefox 33, Venkman *no longer works*, as the APIs which it needs have been removed.
Delete Junk Context Menu Requires Restart
Adds 'Delete Mail Marked as Junk' to folders' right click...
Copy Plain Text Requires Restart
Copies text without formatting...
Easy Get Mail Button Requires Restart
Makes the 'Get new messages' button context-sensitive. Select an account root folder to get messages for that account, any other folder to get messages for all...
InspectorWidget Requires Restart
Adds toolbar button and context menus for invoking the DOM Inspector (DOMi) for either chrome or content elements.
QuickNote Requires Restart
A simple note-taking extension.