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  • Fight the text ads! Element Hiding Helper is a companion extension for Adblock Plus meant to make creating element hiding rules easier.
    807,292 users
  • Personas Plus

    Rated 3 out of 5 stars (951)
    Personas are free, easy-to-install "skins" for Firefox. Personas Plus extends that built-in functionality to give you even more control and easier access to new, popular, and your own favorite Personas.
    429,599 users
  • Allows bidirectional access to Google Calendar
    272,239 users
  • If you are the kind of person who likes to have total control over every aspect of your downloads, "Download Status Bar" is the add-on you are looking for.
    256,030 users
  • Minimizes windows into the system tray.
    250,030 users
  • SQLite Manager

    Rated 5 out of 5 stars (30)
    Manage any SQLite database on your computer.
    199,182 users
  • This extension is for those TB3 users who want the multiple-columns view that TB2 allowed
    180,894 users
  • 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.
    146,603 users
  • Toolbar Buttons

    Rated 4 out of 5 stars (315)
    Adds toolbar buttons to the customize toolbar window in several programs including Firefox, Thunderbird and SeaMonkey. Some of the buttons make commonly preformed actions quicker, others add new functionality.
    142,260 users
  • DOM Inspector

    Rated 5 out of 5 stars (61)
    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.
    138,705 users
  • UnMHT

    Rated 5 out of 5 stars (202)
    UnMHT allows you to view MHT (MHTML) web archive format files, and save complete web pages, including text and graphics, into a single MHT file in Firefox/SeaMonkey.
    88,896 users
  • Switch the signature on/off or choose a new one from your predefined set...
    85,298 users
  • FoxClocks

    Rated 4 out of 5 stars (302)
    FoxClocks shows times around the world - or just your local time - at the bottom of your browser. It deals with daylight saving time so you don't have to.
    73,121 users
  • Quicktext

    Rated 5 out of 5 stars (250)
    Quicktext is an extension for Thunderbird that lets you create templates that can be easily inserted into your own emails.
    72,683 users
  • Exif Viewer

    Rated 4 out of 5 stars (83)
    Displays the Exif and IPTC data in local and remote JPEG images.
    70,566 users
  • MR Tech Toolkit

    Rated 4 out of 5 stars (143)
    (Formerly Local Install) The primary goal of this extension is to provide the tools needed to install and manage extensions and themes locally and tons of other features.

    Note: With Toolkit 6.0 Auto Archiving is fully working in Firefox 2.0 and temp...
    62,817 users
  • Adds the Google Calendar web interface as a new tab directly into Thunderbird. Creating and viewing events works just as it would in a browser like Firefox
    60,665 users
  • This 15KB restartless add-on will add a "File" -> "Restart" menu item and a ctrl/cmd + alt + r hotkey to restart Firefox or Seamonkey.
    43,746 users

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