| FoxyPermissions | | - | | |
| FoxFilter | | - | | |
| FoxBleed | | - | | |
| Fox Web Security | | - | | |
| Form History Control | | - | | |
| Forget that page | | - | | |
| Force AutoComplete Extension | | - | | |
| First Party Isolation | | - | | |
| Firefox Interest Dashboard | | - | | |
| Firecookie | | - | | |
| FireGloves | | - | | |
| FireCrypt | | - | | |
| Fingerfox (SE) | | - | | |
| Fingerfox | | - | | |
| Fake Windows Version for Useragent | | - | | |
| Export Cookies | | - | | |
| Exceptions Exporter | | - | | |
| ExExceptions | | - | | |
| Eraser | | - | | |
| Encrypted Communication | | - | | |
| Empty Cache Button | | - | | |
| Edit Cookies | | - | | |
| Eat My Cookies | | - | | |
| DynamicHistory | | - | | |
| Do Not Save Password | | - | | |
| Disconnect | | - | | |
| Disable Visited Links | | - | | |
| Disable Private Browsing Plus | | - | | |
| Disable Plugin ＆ Mimetype Enumeration | | - | | |
| Disable HTTP Referer at Startup | | - | | |
| Disable DHE | | - | | |
| Descript | | - | | |
| Delete Site History | | - | | |
| Delete Cookies | | - | | |
| Decentraleyes | | - | | |
| Custom History Deleter | | - | | |
| CsFire | | - | | |
| CryptoData | | - | | |
| Cryptext | | - | | |
| CreditCardNanny | | - | | |
| Cookies and HTTP Headers analyser | | - | | |
| Cookies Manager+ | | - | | |
| Cookies Export／import | | - | | |
| Cookiebro | | - | | |
| CookieSwap | | - | | |
| CookieShield | | - | | |
| CookieSafe | | - | | |
| CookieMaster | | - | | |
| CookieMan Context | | - | | |
| CookieKiller | | - | | |