Add-ons
Web and Developer Tools
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DOM Inspector
Requires Restart
DOM Inspector is a tool that can be used to inspect and edit the live DOM of any web document or XUL application. The DOM can be navigated using a two-paned window displaying a variety of different views on the document and all nodes within.
JavaScript Debugger
Requires Restart
As of Firefox 33, Venkman *no longer works*, as the APIs which it needs have been removed.
Venkman is the code name for Mozilla's JavaScript Debugger. Venkman aimed to provide a powerful JavaScript debugging environment for Mozilla based browsers.
Element Hiding Helper for Adblock Plus
Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.
SeaMonkey Debug and QA UI
Requires Restart
Provides Additional Debug and QA UI for SeaMonkey development and testing.
User Agent Switcher
Requires Restart
The User Agent Switcher extension adds a menu and a toolbar button to switch the user agent of a browser.
SQLite Manager
Tiny JavaScript Debugger
TinyJSD is a JavaScript debugger for privileged code running Mozilla products like Firefox, Thunderbird, SeaMonkey. It serves to debug the application as well as extensions written in JavaScript.
Live HTTP Headers
DOM Inspector Plus! [dm]
Requires Restart
Improved DOM Inspector! [dm version]. Box Model new layout & more data, see screenshot!. Horizontal scroll for Dom-Tree, and some more.
Inspects the structure and properties of a window and its contents.
Mnenhy
Requires Restart
The primary goal of the Mnenhy project is to make some enhancements to SeaMonkey MailNews/Thunderbird, since there're still plenty of comfort functions missing if compared to Netscape 4.x and other mail and news clients.
RefControl
Requires Restart
Control what gets sent as the HTTP Referer on a per-site basis.
WorldIP - Geo Add-on with Security Features
Requires Restart
Professional Geo Add-on with security features and advanced network tools. Anti-phishing. Protection against DNS spoofing and fake sites. All DNS records for domain. The real location of web server, country flag, extended information about datacenter
HttpFox
MonkeyFix
Requires Restart
Fixes up numerous SeaMonkey browser interface issues (eg. adding support for popup ALT attributes), as well as adding some handy features for developers and power users (eg. configure source viewer, work online/offline).
Firesizer
Requires Restart
Allows you to resize the window to specific dimensions.
NOTE: Users of Firefox 29 and above must install "The Addon Bar" extension to use this, as Firesizer uses the add-on bar that has been removed in Firefox 29.
Dafizilla Table2Clipboard
Requires Restart
Mozilla applications allow to select rows and columns from a table simply pressing Control key and picking rows/columns with left mouse button.
The selection can be copied to clipboard but the original table disposition is lost making ugly results wh...
Link Properties Plus
Requires Restart
Provides extended link properties: size of linked file, last modified time, etc.
Restartless Restart
This 15KB restartless add-on will add a "File" -> "Restart" menu item and a ctrl/cmd + alt + r hotkey to restart Firefox or Seamonkey.
Remote XUL Manager
Manages the Remote XUL whitelist to allow websites and local files to load XUL content. For versions compatible with Firefox 41 and lower, see All Versions page below.
IE Tab + (FF 8+, 7, 6, 5, 4, 3.6, 3.5, SeaMonkey)
Requires Restart
IE Tab + is an enhanced version of IE Tab. It supports FF 3.5 or greater, integrates IE Tab with Adblock Plus in the IE Tab engine, and synchronizes cookies between IE and Firefox. You can easily import settings from the original IE Tab into IE Tab +
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