Android Add-ons

FlashGot Mass Downloader by Giorgio Maone

Download all the links, movies and audio clips of a page at the maximum speed with a single click, using the most popular, lightweight and reliable external download managers.

Password Exporter by Justin Scott (fligtar), Jorge Villalobos

This add-on allows you to export your saved passwords and disabled login hosts using XML or CSV files that can be imported later.

Note: This add-on won't work in Firefox 57. It may eventually if the APIs to access passwords are implemented.

Element Hiding Helper for Adblock Plus by Felix Dahlke

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

Toolbar Buttons by Button Guy

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.

Firesizer by orev

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.

Compact Menu 2 by Milly

Add a compact menu button to the navigation toolbar, and hide the menu bar.

AutoPager by Wind Li

AutoPager automatically loads next pages when you reach the end of a page. It works on a ton of sites,Google,Yahoo..
It works well with most other add-ons adblock plus, WOT and most of the greasemonkey scripts.
You can also try AutoPagerLite.

CustomizeGoogle by CustomizeGoogle

CustomizeGoogle enhances Google by adding information and removing unwanted information.

Collector's Note Da kann man manches in Google abschalten - Werbung z.B....

KOLOBOK Smiles for Firefox by Hyron

Firefox extension for KOLOBOK-Style smiles (http://www.kolobok.us/)
(based on Smiley Extra version 4 by James Baker)
Toolbar to use kolobok smiles in forums and blogs.

CuteMenus - Crystal SVG by mrtech, Static_Nexus, others

Note from Mozilla: This add-on has been discontinued. Try Menu Icons Plus instead.

Adds icons to all menus along with some other features...

MR Tech Toolkit by mrtech

(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...

Splash! by mrtech, slyfox

Adds a splash screen to most Mozilla and Mozilla Based products. Supports sound, opacity, CSS customization, custom images, and much more. You can add {appVersion}, {buildID} and {userAgent} to the loading text and it will be filled in for you.

Collector's Note Das Add ist absolut sinnfrei - aaber schön! Vor/beim Start von FF kommt ein Splash-Screen - den kann man individalisieren. MIt PNGs, JPGs usw. Bei der Größe muß man halt schauen - ich nehm so bis 300 Pixel - geht aber auch größer. Geräusche kann man auch einstellen, bei mir startet da ein Auto.

BBCodeXtra by flod

(Sorry, no plans to port this add-on to Webextensions)
BBCodeXtra is an extension, compatible with Mozilla FireFox (up to 57) and Seamonkey, which adds to the context menu new commands to insert BBCode/Html/XHtml codes in an easy and fast way...

HashColouredTabs+ by John P Baker

Improves tab identification by providing a small colored icon for any site which doesn't have its own 'site icon'.
★ 'favicon' now also shown in history and bookmarks ★