Firefox Addons
From charlesreid1
Listed in order of importance/usefulness.
Contents
NoScript
An absolutely essential Firefox addon, this is the number one reason for not switching to another browser. NoScript takes some getting used to initially, and can screw you up at first, but once you learn to integrate it, it's essential. It amazes me how much unnecessary script crap runs in the background of every web page, and NoScript not only makes pages load faster, but keeps a lot of under-the-table-data from flying around (like, your Facebook credentials - CREEPY).
The way I use NoScript is, I disable all popup warnings and message bars and all that stuff. I have a little NoScript icon in the bottom-right corner of every Firefox window. If there are any scripts blocked on the page I'm visiting, the NoScript icon is an "S" with a red strikethrough. I will allow pages I visit regularly (Gmail, New York Times, YouTube, etc.). To allow scripts, you can click the "S" and pick the sites you want to allow.
If I am visiting any website with a shopping cart, or where I am purchasing something, I will click the "S", which brings up the NoScript menu, and pick "Temporarily Allow All". This will prevent any scripts essential for the purchase, but not within the domain name (like PayPal), from breaking.
Another nice feature is, if there are embedded Flash objects, they show up as greyed-out NoScript boxes, and to allow them to run, you simply click them.
https://addons.mozilla.org/en-US/firefox/addon/noscript/
Adblock Plus
This addon provides much-needed relief from obnoxious advertisements that are EVERYWHERE on the web. One of my favorite features is that if there is an ad that it somehow misses, I can right-click on the ad and make sure it never shows up again.
https://addons.mozilla.org/en-US/firefox/addon/adblock-plus/
Xmarks
After NoScript and AdBlock, this is the next addon that I install anytime I have a new system or new version of Firefox. Xmarks helps me sync my bookmarks across computers, so I can take all my bookmarks with me. I can also access them from the web, meaning I don't have to be on my own computer to access my bookmarks - I can log into Xmarks' webpage from any browser and any computer, and I can see all of my bookmarks in a list format.
https://addons.mozilla.org/en-US/firefox/addon/xmarks-sync/
Evernote Web Clipper
This is a very, very useful Firefox addon that allows me to clip things I read online straight to Evernote. It can be very laggy/slow sometimes, but if Evernote is running in the background it tends to work a little better.
I have a "Clip to Evernote" button on my Navigation bar, and I routinely highlight text from interesting articles, or pictures I like and want to save, or whatever, and click the "Clip to Evernote" button to create a new note with the selected text as the content. (Another advantage is it adds the web address of the web page to the note's metadata).
https://addons.mozilla.org/en-US/firefox/addon/evernote-web-clipper/
TinEye Reverse Image Search
Adds an item to the right-click menu for any image, to perform a reverse-image search using TinEye. Can come in very handy.
https://addons.mozilla.org/en-US/firefox/addon/tineye-reverse-image-search/
Readability
A very nice and very simple tool that makes reading much easier and more enjoyable. It gets rid of all the sidebar/advertisement/navigation clutter and gives you a nice, clean page of text. Absolutely essential for distraction-free reading at blogs, news sites, etc.
https://addons.mozilla.org/en-US/firefox/addon/readability/
Firebug
Helps with PHP and HTML development, esp. with quick browsing of HTML source to get form names, element names, etc. Has an extremely handy interface, all you have to do is put the mouse over an element and Firebug brings up the HTML code that is associated with that element. You can also use it to inspect GET and POST data, cookie data, etc. Very robust and handy addon.
Live HTTP Headers
Extremely useful browser that shows you all the information/communication happening between client (your browser) and server (the server hosting the web page you are visiting). Shows all of the information that's flying back and forth every time something is requested (e.g. User Agent, Web Server type, cookie name/content, etc.)
http://livehttpheaders.mozdev.org/
TamperData
Allows you to tamper with POST and GET data being sent to web servers.
Web Developer
Redundant if you have Live HTTP Headers (a much better extension) and/or Firebug (a much better user interface), but you can never have too many tools.
http://chrispederick.com/work/web-developer/
Greasemonkey
A useful addon that allows you to run custom post-processing scripts for various web sites. This is extremely useful to, say, get rid of an ugly menu bar, remove frames, rearrange elements, etc. This is extremely useful if there is a site you regularly visit that is really, really ugly and you just HAVE to fix it.
Torbutton
This is a Firefox addon that integrates with the Vidalia Client (on Mac), and allows you to browse the web via the Tor network. This provides you with an anonymous internet proxy, so that your IP address isn't linked to your browsing. Essential if you want your browsing to be private, but there is a significant increase in loading time, since traffic is being routed through random servers scattered across the globe.
https://addons.mozilla.org/en-US/firefox/addon/torbutton/
Searchbar Autosize
One of the things about Firefox that bothered me was the behavior of the search bar. It took up a lot of room, but I didn't use it most of the time. This addon addresses this minor irritation by making the searchbar tiny until it is activated, and when it is activated it makes the search bar large.
https://addons.mozilla.org/en-US/firefox/addon/searchbar-autosizer/
(Not available for Firefox 4 as of May 2011
Tab Mix Plus
This is a nice addon that makes the tabs behave a little smarter. You can do things like show the percentage of the page that's loaded as a color status bar in the tab title, have unread tabs show up as a unique color, and do some fancy tab-rearrangement tricks.
https://addons.mozilla.org/en-US/firefox/addon/tab-mix-plus/
YouTube Comment Snob
This is a handy addon that I use to eliminate all YouTube comments. YouTube comments are always obnoxious, annoying, and stupid, and I don't even want to look at them.
https://addons.mozilla.org/en-US/firefox/addon/youtube-comment-snob/
FoxLingo
A handy translation addon that is particularly useful if you like to get some of your news from non-English speaking sources. While any automated translation tool is bound to perform poorly in some situations, FoxLingo does a good enough job for me.
https://addons.mozilla.org/en-US/firefox/addon/foxlingo-translator-dictionary/
FlagFox
Displays an icon in the toolbar with a flag that indicates the geographical location of the web server you're currently visiting.
Paranoia Package
Collection of addons that are handy for maintaining your privacy and exercising your paranoia to the fullest.
https://addons.mozilla.org/en-US/firefox/collections/Siren69/paranoiapackage/