| Chain Duck | | - | | |
| CenterTube | | - | | |
| Camideo Video Search | | - | | |
| Calilay | | - | | |
| CacheIt! | | - | | |
| CL Pics | | - | | |
| Button for Amazon | | - | | |
| BuiltWith Tab | | - | | |
| BugzillaJS - Tweaks for Bugzilla | | - | | |
| BugMeNot | | - | | |
| Bug | | - | | |
| BrowsIn | | - | | |
| Boorumate | | - | | |
| Booru Slideshow | | - | | |
| Booru Extractor 3 | | - | | |
| Booru Extractor | | - | | |
| Blue Google Theme | | - | | |
| Black Youtube Theme | | - | | |
| Black Skin | | - | | |
| Black Google Theme | | - | | |
| Bitcoin Price Ticker | | - | | |
| Bitbucket Issues convenience | | - | | |
| BitDefender QuickScanner | | - | | |
| Bing to Duck redirect | | - | | |
| Bing Search for Firefox | | - | | |
| Better MXR | | - | | |
| Better Gmail 2 | | - | | |
| Bestsellers and Search on Rakuten， Amazon and Yahoo! Shopping | | - | | |
| Best Free Image Hosts | | - | | |
| Beautify Google | | - | | |
| Beautify | | - | | |
| Bandcamp Volume Slider | | - | | |
| Bandcamp Volume | | - | | |
| Bandcamp New Tab | | - | | |
| BabelFish | | - | | |
| BINGO! Search | | - | | |
| BIGLOBEゲートβ | | - | | |
| BGIPEO | | - | | |
| Awesomebar Bugzilla Suggestions | | - | | |
| Auto Price Checker | | - | | |
| Ask Mona Extension | | - | | |
| Ascii2d Image Search | | - | | |
| Are4Are | | - | | |
| Archiveror | | - | | |
| Archiver Menu | | - | | |
| ArchiveThis | | - | | |
| Archive Everything | | - | | |
| AnkoLauncher | | - | | |
| AniWeather | | - | | |
| Android Desktop Notifications | | - | | |