Extensions
If you don't find a certain extension here, and you're feeling courageous, I have a tutorial on how to hack extensions to make them compatible with SeaMonkey.
Note: This page wouldn't have been possible without the contributions of the people posting at MozillaZine. Thanks, everyone.
Last updated: 7 August 2009
| Extension | Notes | Author | Compatibility |
|---|---|---|---|
| Aardvark | None | Karmatics.com | SeaMonkey 1.0 - 1.1 |
| about:kitchensink | See bug#122411 | Mook | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Accountex | Not all account information is exported | Michael Otto, Philip Chee | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Adblock | None | The Adblock Crew,Michael McDonald | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| Adblock Plus | None | Wladimir Palant | SeaMonkey 1.0 - 1.1 |
| addressContext | None | Mike Krieger, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Allow HTML temp | None | Alexander Ihrig | SeaMonkey 1.0 - 1.1 |
| Always Remember Password | None | Eric Hamiter | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Attachment Extractor | Requires xSidebar for the options dialog | eviljeff, Philip Chee | SeaMonkey 1.1 |
| Attachment Sizes | None | Frank DiLecce, Philip Chee | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| AutoCopy | None | Michael Lidman | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| AutoHide | None | Jochen | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| autoHideStatusbar | Requires xSidebar | Regis Caspar, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Back to Top | Requires xSidebar for the options dialog | Chuck Baker, BenoitRen | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Bandwidth Tester | None | Jeremy Gillick | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| BBCode | None | Jed Brown | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| BBCodeXtra | None | ExtenZilla | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Better Gmail | None | Gina Trapani | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| BiDi Mail UI | None | The BiDi Mail UI Team | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| BookmarksHome | Only version 1.2.10 is compatible | Jeroen Groenenboom, Dimiter Dimitrov, Josh Powell | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| BugMeNot | None | Eric Hamiter, Philip Chee | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Cache Fixer | None | Danil Ivanov | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| CacheViewer | None | benki, BenoitRen | SeaMonkey 1.0 - 1.1 |
| Check4Change | None | Ronen Zilberman | SeaMonkey 1.0 - 1.1 |
| Checky | None | Joachim Schreiber | Mozilla 1.5.1 - 1.7, SeaMonkey 1.0 - 1.1 |
| ChromEdit | None | Chris Neale | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| ChromEdit Plus | None | Jim Newberry | SeaMonkey 1.0 - 1.1 |
| Clear Private Data | None | Jim Newberry | SeaMonkey 1.0 - 1.1 |
| Clines | You can also play it in the browser or with XULRunner | arno | SeaMonkey 1.0 - 1.1 |
| Clippings | None | AE Creations | SeaMonkey 1.1 |
| Clone Window | None | pikey, BenoitRen, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| ColorZilla | Needs xpcom.dll in the components directory for the eyedropper to work | Alex Sirota | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| ConfigDate | None | Alexander Ihrig | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| ConQuery | None | Vasa Maximov | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| Console² | None | zeniko, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Context Highlight | None | Ben Basson, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Context Search | None | Ben Basson, Philip Chee | SeaMonkey 1.0 - 1.1 |
| CookieCuller | None | Dan Yamaoka | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| CookieSwap | None | Steve Tine | SeaMonkey 1.0 - 1.1 |
| Copy Link Name | None | Captain Caveman | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Copy Plain Text | None | Jeremy Gillick, Philip Chee | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Copy URL + | None | Philip Mateescu | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| CS Lite | None | Ron Beckman | SeaMonkey 1.1 |
| CustomizeGoogle | None | CustomizeGoogle, Jaisen | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Date Picker/Calendar | None | James Cook, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| del.icio.us Complete | None | The del.icio.us Complete Team, Philip Chee | SeaMonkey 1.0 - 1.1 |
| DerBrowserTimer | Charles Melhorn, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 | |
| deskCut | Version 0.4.1.3 is the last compatible one. It ignores your locale if it's the first extension installed | Evan Eveland | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Dict | None | David Costanzo | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| Dictionary Switcher | None | Dao Gottwald, Philip Chee | SeaMonkey 1.1 |
| Diggler | Version 0.6 is the last compatible one | Adam Lock | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Display Mail User Agent | Needs either Mnenhy or Enigmail installed to work | Christian Weiske, Jaisen | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Download Statusbar | Version 0.8 is the last compatible one | Devon Jensen | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| DownThemAll | Requires xSidebar | Federico Parodi and Stefano Verna, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Drag And Drop Upload | None | Emanuele Ruffaldi, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Duplicate Contact Manager | None | Marian Steinbach, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Duplicate Tab | None | Twanno | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| EasySearch | None | Andreas Andersson, ZonkSJx | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| Email This! Bookmarklet Extension | Requires xSidebar | Arthur Sabintsev | SeaMonkey 1.0 - 1.1 |
| Enigmail | None | Patrick Brunschwig | SeaMonkey 1.0 - 1.1 |
| Execute JS | None | Rudolf Noe | SeaMonkey 1.0 - 1.1 |
| Extension Developer's Extension | This extension is in perpetual beta | Ted Mielczarek | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| EZNav | None | Devon Jensen | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| FareCompare (FareFirst) | None | FareCompare, BenoitRen | SeaMonkey 1.0 - 1.1 |
| Feedview | None | Tom Germeau, deathburger | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Fetch Text URL | None | Jeff Chien | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| FireForm | The new icons don't work | Jean-Marc Bastide, John Parsons | SeaMonkey 1.0 - 1.1 |
| FireFTP | None | Mime Cuvalo, Philip Chee | SeaMonkey 1.0 - 1.1 |
| FlagFox | None | Joseph Birr-Pixton, deathburger | SeaMonkey 1.0 - 1.1 |
| Flashblock | None | The Flashblock Team | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| FlashGot | None | Giorgio Maone, Round Two | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Flat Bookmark Editing | None | Chris Houser, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Folder Account | None | Christopher Eykamp, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Folder Flags | None | Ryan Lee, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Folderpane Tools | None | Christopher Eykamp, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Forecastfox | Version 0.9.3 is the last compatible one | The Forecastfox Team | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| ForecastFox Enhanced | None | The Forecastfox Team, Aaron Sarna, A.C., Philip Chee | Mozilla 1.5 - 1.7, SeaMonkey 1.0 - 1.1 |
| Formfiller | None | Jason Baldus, BenoitRen | SeaMonkey 1.0 - 1.1 |
| Forumzilla | None | Myk Melez | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| FoxClocks | None | Andy McDonald, Philip Chee | SeaMonkey 1.0 - 1.1 |
| FoxyTunes | None | Alex Sirota | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Fuller Screen | None | Daniel Glazman | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| FxIF | None | Ted Mielczarek | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| GameFAQs Toolbar | None | Michael Dorman, Anatoly Ivanov, Ramiz Qureshi, BenoitRen | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| GameFOX TK | Requires xSidebar for the options dialog | Abdullah A, BenoitRen | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Gcache | None | Kristof Polleunis | Mozilla 1.5 - 1.7, SeaMonkey 1.0 - 1.1 |
| Gmail Notifier | None | Doron Rosenberg | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Google Pagerank Status | None | Stephane Queraud, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Googlebar | None | John Woods | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Greasemonkey | Requires xSidebar | The Greasemonkey Team, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Groowe Search Toolbar | None | Milos Mileusnic | Mozilla 1.5 - 1.7, SeaMonkey 1.0 - 1.1 |
| Gspace | None | Rahul Jonna, tnarik, BenoitRen, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Habari Xenu | None | Thaths | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Home Button | None | Reidar Djupvik | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| HTML Validator | None | Marc Gueury | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| IE Tab | Beta versions stopped being compatible at a certain point | PCMan (Hong Jen Yee), yuoo2k | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| IE View | Viewing Page Source results in an alert window noting "NO BUNDLE" before it appears | Paul Roub | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Image Zoom | Migrates badly between versions, reinstall after migration | Jason Adams | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| ImageShack right-click | None | ImageShack, deathburger | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| ImportExportTools (MboxImport) | None | Paolo Kaosmos, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| infoRSS | None | Didier Ernotte | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| JS Console output redirector | None | TBlack | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| JSView | None | Ron Beckman | SeaMonkey 1.0 - 1.1 |
| Jump Link | None | Philip Mateescu | SeaMonkey 1.0 - 1.1 |
| keywordManager | Requires xSidebar | Regis Caspar, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Launchy | None | Henrik Gemal | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| Leak Monitor | None | David Baron | SeaMonkey 1.0 - 1.1 |
| Linky | None | Henrik Gemal | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| Link Visitor | None | Billy | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Linkfilter Toolbar | None | deathburger | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| Linkification | None | y5 | Mozilla 1.7, SeaMonkey 1.0 |
| Live HTTP Headers | None | Daniel Savard | Mozilla 1.1 - 1.7, SeaMonkey 1.0 - 1.1 |
| LookOut | None | Aron Rubin, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Lorem Ipsum Content Generator | None | Jeremy Gillick | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| MailClassifier | None | Emanuele Sabellico, Daniele Repici | SeaMonkey 1.1 |
| mailTagger | Requires xSidebar for the options dialog | Ons Besbes, BenoitRen | SeaMonkey 1.0 - 1.1 |
| MeasureIt | None | Kevin Freitas, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| MediaPlayerConnectivity | None | Sethnakht | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Menu Editor | None | Devon Jensen, Nickolay Ponomarev, Philip Chee | SeaMonkey 1.0 - 1.1 |
| MessageFaces | None | Jens Bannmann, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| MonkeyMenu | None | Mark Bokil | SeaMonkey 1.0 - 1.1 |
| Mouse Gestures | None | Optimoz Team | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| Mouseless Browsing | None | Rudolf Noe, BenoitRen | SeaMonkey 1.0 - 1.1 |
| MoveThrobber | None | Aaron Spuler | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| MozEX | None | Tomas Styblo, neuron | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Mnenhy | None | Mnyromyr | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| MR Tech's Disable XPI Install Delay | None | Mel Reyes (aka: mrtech) | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| MR Tech's Local Install | None | Mel Reyes (aka: mrtech) | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| MultiZilla | None | HJ van Rantwijk | SeaMonkey 1.0 - 1.1 |
| Named Anchors | Version 0.2.1 is the last compatible one | Jeroen Peters | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Neo Diggler | None | Neil Bird, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Net Usage Item | None | critter | SeaMonkey 1.0 - 1.1 |
| NewsFox | Requires xSidebar | Andy Frank, Andrey Gromyko, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| No New Window on Double Click | None | chuonthis, Philip Chee | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| NoScript | None | Giorgio Maone | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| NoSquint | None | Jason Tackaberry, Philip Chee | SeaMonkey 1.1 |
| Nostalgy | None | Alain Frisch, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Nuke Anything | None | Ted Mielczarek | Mozilla 1.5 - 1.7, SeaMonkey 1.0 - 1.1 |
| Nuke Anything Enhanced | None | Patrick, Philip Chee, therube | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Ook | None | Chris Neale | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| Open in browser | None | Sylvain Pasche, Stanimir Stamenkov | SeaMonkey 1.0 - 1.1 |
| OpenDownload | None | Jeremy Gillick | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Optimoz Tweaks | None | Optimoz Team | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| Organize Status Bar | None | John Hansen, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Page Animation | None | Daniel Matejka | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| PageStyle2Tab | None | Sethnakht | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Paste and Go | None | Jens Bannmann | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| Paste and Go 2 | None | Holio Lin, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Paste IP | None | Michael Newton | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Paste Email | None | Chuck Baker, BenoitRen | SeaMonkey 1.0 - 1.1 |
| PhishTank SiteChecker Classic Mod | None | GS! Networks | SeaMonkey 1.0 - 1.1 |
| Performancing | None | Performancing.com, BenoitRen | SeaMonkey 1.0 - 1.1 |
| PlainOldFavorites | None | Alex Sirota, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| PrefBar | None | Aaron Andersen, Manuel Reimer | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| Preferential | None | Stephen Bounds | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| ProxyButton | None | Oleg Ivanov, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| QuickJava | None | Doug G, Philip Chee | SeaMonkey 1.0 - 1.1 |
| QuickNote | None | Jed Brown, Nickolay Ponomarev | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| Quote Colors | None | Malte Ruecker | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Rainbowpicker | None | Toad King | SeaMonkey 1.0 - 1.1 |
| refspoof | None | Boyd, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Reload Every | Jaap Haitsma, Philip Chee | SeaMonkey 1.0 - 1.1 | |
| ReminderFox | None | Tom Mutdosch, Daniel Lee, Philip Chee | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Remote Image Cache | None | Einar Egilsson, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Remove Cookie(s) for Site | None | Dwipal | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Remove Duplicate Messages (Alternate) | None | Eyal Rozenberg | SeaMonkey 1.0 - 1.1 |
| Remove It Permanently | None | Jerome O'Flaherty | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Resizable Textarea | None | Raik Juergens, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Resurrect Pages | None | Anthony Lieuallen, Philip Chee | SeaMonkey 1.0 - 1.1 |
| rikaichan | None | jon | SeaMonkey 1.0 - 1.1 |
| Sage | Requires xSidebar | The Sage Team, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Save As Image | Requires xSidebar for its options dialog | Rowan Lewis | SeaMonkey 1.1 |
| ScribeFire | None | Christopher Finke, Philip Chee | SeaMonkey 1.1 |
| SeaNotes | None | Jim Newberry | SeaMonkey 1.0 - 1.1 |
| Search Engine Wizard | None | Milx | SeaMonkey 1.0 - 1.1 |
| Send Filter | None | xzer lr | SeaMonkey 1.0 - 1.1 |
| Session Manager | Depends on Chrash Recovery | zeniko | SeaMonkey 1.0 - 1.1 |
| Show Anchors | None | PCDingo, Philip Chee | SeaMonkey 1.1 |
| Show Image | None | Cheng Khoon, BenoitRen | SeaMonkey 1.0 - 1.1 |
| Show IP | None | Jan Dittmer | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| Showcase | Requires xSidebar for the options dialog and the sidebar | µWorks | SeaMonkey 1.0 - 1.1 |
| Signature | None | miek, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Single Window | None | Aaron Spuler | Mozilla 1.0 - Mozilla 1.7 - 1.1 |
| SmoothWheel | None | Avi Halachmi | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| Snap Links | None | Pedro Fonseca, BenoitRen | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| SpellBound | None | Robert Strong | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| SpiderZilla | None | BatBat | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| SQLite Manager | None | Mrinal Kant, Philip Chee | SeaMonkey 1.1 |
| Statusable | None | Patrice Levesque, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Statusbar Clock | None | Cosmic Cat Creations, Philip Chee | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Storage Inspector | None | Racer, Philip Chee | SeaMonkey 1.1 |
| Stylish | None | Jason Barnabe (np), Philip Chee | SeaMonkey 1.0 - 1.1 |
| Sun Cult | Requires xSidebar | Karel Sommer, BenoitRen | SeaMonkey 1.0 - 1.1 |
| Switch Proxy | None | Jeremy Gillick | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Tab Clicking Options | None | Twanno | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Tab Effect | Windows only, uses DirectX 8 | satohk, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Tab Scroller | None | Jochen | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| Tab X | None | Stephen Clavering, BenoitRen | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Tabbrowser Extensions | None | Piro | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Tabinta | None | Balint Endrey | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Tabs Menu | None | Mikel Ward, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Tabs Open Relative | None | John Mellor | SeaMonkey 1.0 - 1.1 |
| Tag Dialog | None | teramako, Philip Chee | SeaMonkey 1.1 |
| TagZilla | None | David Perry, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Tails Export | None | Robert de Bruin, Philip Chee | SeaMonkey 1.0 - 1.1 |
| text/plain | None | Gilles Durys | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| TextZoom | None | Cosmic Cat Creations, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Themer | None | Chris Neale | Mozilla 1.5 - 1.7, SeaMonkey 1.0 - 1.1 |
| Tidy Browser Button | None | Colin Purves, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Timestamp | Version 0.3 is the last compatible one, unless you hack in an install.js file | Jeroen Peters | SeaMonkey 1.0 - 1.1 |
| TinyUrl Creator | None | Jeremy Gillick | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| Titlebar Tweaks | None | Cosmic Cat Creations | SeaMonkey 1.0 - 1.1 |
| Toggle Word Wrap | None | Kaspar Brand, Philip Chee | SeaMonkey 1.0 - 1.1 |
| Tooltip Enhancer | None | Jochen | SeaMonkey 1.0 - 1.1 |
| Trashmail.net | None | Stephan Ferraro, BenoitRen | SeaMonkey 1.0 - 1.1 |
| undoclosetab | None | Dorando | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Unhide Passwords | None | Norbert Wienholz | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Unselect Message | None | Michael Buschbeck, Philip Chee | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| URI id | This extension has become obsolete because of @-moz-document, available in SeaMonkey 1.0 and newer | Chris Neale | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| User Agent Switcher | None | Chris Pederick | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| userChrome.js | None | zeniko | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Viamatic foXpose | None | Viamatic Softwares, Philip Chee | SeaMonkey 1.0 - 1.1 |
| VideoDownloader | Requires xSidebar | Javi Moya, BenoitRen | SeaMonkey 1.0 - 1.1 |
| Video DownloadHelper | None | mig, Philip Chee | SeaMonkey 1.0 - 1.1 |
| View Cookies | None | Edwin Martin, BenoitRen | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| View Dependencies | None | Florian Quèze, Philip Chee | Mozilla 1.6 - 1.7, SeaMonkey 1.0 - 1.1 |
| View Formatted Source | None | Felix Ritter | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| View Source in Tab | None | LouCypher, deathburger | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| ViewSourceWith | None | Davide Ficano | Mozilla 1.7, SeaMonkey 1.0 - 1.1 |
| Web Developer | None | Chris Pederick | Mozilla 1.0 - 1.7, SeaMonkey 1.0 - 1.1 |
| Webmail | Requires xSidebar for the options dialog | Andrew Archer | SeaMonkey 1.0 - 1.1 |
| XpcomViewer | None | Ondrej Donek | SeaMonkey 1.0 - 1.1 |
| XNote | None | Pierre-André Galmes, Philip Chee | SeaMonkey 1.0 - 1.1 |
| xSidebar | None | Philip Chee | SeaMonkey 1.0 - 1.1 |
| XUL MSN Messenger | None | Syko, BenoitRen | Mozilla 1.4 - 1.7, SeaMonkey 1.0 - 1.1 |
| Zombie Keys | None | Kai Bolay, Philip Chee | SeaMonkey 1.0 - 1.1 |
