Open Tabs Next to Current No Restart
Open new tabs always to the right of the current one.
Pin Unpin Tab No Restart
Pin or unpin current tab through new, cooler ways:
1. Customizable keyboard shortcut. Default is Alt-P
2. Firefox Developer Command line -> 'pintab' & 'unpintab'
UPDATE: Commands don't work anymore. They are disabled from version 1.0.
Custom UserAgent String No Restart
Add a custom useragent string for desired URLs or domains.
Opens "Downloads" manager in tab from Tools menu or automatically when a download starts (default). See Options for more choices.
Open in IE™ (Internet Explorer) No Restart
Open links in Internet Explorer
Stratiform is the ultimate user friendly customization add-on for Firefox. It puts the power in the average user's hands to customize the browser's look.
Tab Tree No Restart
Tab Tree shows your tabs in the form of a tree structure. And also makes the user interface compact (optionally) to allow more space for the Web.
Firefox 6 introduces new Permissions Manager which you can find under URL "about:permissions". This add-on adds link to the menu where you cannot find link to this manager at this moment.
Session Sync No Restart
Save sessions as bookmarks and sync them through Firefox Sync.
Manage, edit, save, restore.
Session-Sync will automatically detect updates and display updated sessions across multiple machines.
Load Tab on select No Restart
Stops background tabs from loading until you select them.
Office-Online No Restart
A basic office online addon
TubeCast No Restart
For those that have smart TV's and use the great TubeCast application available on Windows 10.
Owl - For comfortable reading No Restart
An add-on to make online reading easy.
This add-on makes reading comfortable by dimming the background and transforming the theme of the page into a darker one.
Keep up with time.
A minimalist clock on the new tab page showing the current time, date, and weather. Both the background colour and the text colour are fully customizable.
Simplified Tab Groups No Restart
A Firefox addon that provides tab grouping features similar to the removed TabView/TabGroups/Panorama features with a different UI. This add-on is able to manage tab groups created by Panorama.
Thin Tabs No Restart
Extremely thin tabs optimized for the squared variants of Classic Theme Restorer.
I fear it will look awful with the default Australis tabs, so be warned.
With version 1.1 an option dialog with various customization options has been added.
Open With Opera No Restart
Open With Opera sends pages, links, tabs and images from Mozilla Firefox to Opera.
Window Master No Restart
Functionality for multiple screens and windows. Easily open links in other windows or on other screens, move or merge tabs, and move or merge entire windows. With graphical controls for grid positioning.
Exports Firefox sessions to HTML files or saves them to your bookmarks. If your session includes tab groups, your tabs are grouped accordingly.
Transforms "List all tabs" menu to do closing, loading, unloading, moving of single/multiple tabs. Search tab titles or *content* (remember "Find In Tabs"?), visited tabs history, find duplicate tabs - very helpful for mega-tab users. And more...