Add-ons

DownThemAll! by Nils Maier, Federico Parodi, others

The first and only download manager/accelerator built inside Firefox!

Collector's Note Download easily lots of links in a webpage, selecting they with the mouse or using regular expressions using the full url of the files you need to download.

User Agent Switcher by chrispederick

The User Agent Switcher extension adds a menu and a toolbar button to switch the user agent of a browser.

Collector's Note Allows you to change easily the User Agent of the Browser.

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.

Live HTTP Headers by Daniel Savard, Nikolas Co

View HTTP headers of a page and while browsing.

Collector's Note Shows the headers sent by the browser and received from the Server for all the browser request. Firebug of the Developer console does it too, but this extension it's not affected when a webpage refreshes or changes to another.

Session Manager by Michael Kraft

Session Manager saves and restores the state of all or some windows - either when you want it or automatically at startup and after crashes. It can also automatically save the state of open windows individually.