I'll just paste a blog post I wrote up a while ago.
AdblockPretty much any heavy web user is likely tired of annoying advertisements, and I’m no exception. Adblock combined with the next extension takes care of pretty much every ad I am ever likely to see.
Adblock Filterset.G updater
This little tool simply fetches frequent and thorough blacklists of ad sites and servers. It really is just a set-and-forget thing.
BugMeNot
Ever get annoyed by sites that want you to register to see their content or read more? The BugMeNot extension lets you bypass compulsory web registration via Firefox’s right-click context menu.
It really is as simple as that. Though if it’s a more obscure site it might come up dry, for most there’ll be pre-existing info for you to use.
ColorZilla
Colorzilla does what I thought the name suggested when I first heard of it - It’s a great colour picking tool.
It’ll let you pick colours from anywhere in your Firefox window - even the window itself, such as the menu / address bar and so on. You can zoom the page, create, use and save palettes. It’s handy for somebody into web design such as me, and is a great step up from the old method of screenshotting a site, pasting it into an image editing app and then picking colours from there.
CustomizeGoogle
Does exactly what it says on the tin: thorough customisation of everything google related.
This handles pretty much everything you could think of when wanting to tweak google’s behaviour. It is essentially a customizable rounding up of the best google customization greasemonkey scripts with a handy frontend. Recommended.
DownThemAll!
Saving the task of using a bloated, spyware and unneccessarily standalone manager such as FlashGet, DownThemAll! runs right inside and integrates with Firefox.
All the expected features are there, resuming, acceleration, filtering by name or extension, link crawling and so on.
Fasterfox
Fasterfox is not without some controversy, and I block it myself, though I keep it around, primarily for a small feature: the page load timer.
FaviconizeTab
Just a neat little extension that lets you shrink a tab you’re not currently using to just its favicon. I use it when for example when I’m using a file upload service and want to keep the upload tab out of the way whilst browsing in others.
Fission
Ever since installing Safari for windows, I thought having the loading bar be in the address bar was a great idea, so looked around for an extension for it. Sure enough, there was fission. Simple and much more practical.
Flashblock
Since adblock gets all of the ads, that isn’t the purpose flashblock serves for me. I prefer to browse without annoying autplaying youtube videos (I like to open a set of youtube videos and then watch them, I assume others browse this way, in which case the autoplaying would be annoying) and especially loud badly compressed autostarting emo music on myspace profiles.
Flash objects are replaced by a box the size of the object with a button. Clicking anywhere in this will enable the object and it’ll work like normal. Very handy.
Greasemonkey
Greasemonkey allows you to run specialized scripts on certain sites to customise the look or add or remove functionality or various other tweaks. These scripts are called user scripts, and there are literally thousands of greasemonkey scripts available. Greasemonkey’s capabilities are pracitcally limitless
ImageZoom
ImageZoom simply lets you resize images, either alone or as part of a web page. It’s handy when you sometimes might want a closer look at something. I sometimes find myself just playing around with it when I’m bored. It has advanced options, and I’ve configured mine so that all I need do is hold a click on an image and simpy scroll to resize.
Imageshack right-click
As a frequent imageshack user (my account is approaching 6,000 images in size as of this writing), this extension is wholly useful. Simply right click on any image anywhere and you can send it straight to imageshack. Great for avoiding hotlinking or simply saving an image for later.
Locationbar2
Locationbar transforms your address bar into much more than just an indication of the URL. Each directory into a site becomes a clickable link, making it great for browsing around file folders or sites with a nice directory tree structure. It also lets you tweak appearance; I’ve got emphasis on the domain, as well as removing the protocol (http:// or https:// and so on, https:// is signified by a yellow address bar anyway).
Menu Editor
By far one of the coolest extensions for customising Firefox’s appearance and functionality. After all, who actually uses the context menu options such as “Send Image”? I certainly don’t, and as such have removed it along with other clutter. Combined with the Tiny Menu extension shown later on, this lets me really compact down my Firefox window whilst still keeping optimal functionality.
MinimizeToTray
Likely a matter of personal preference for people, but when I minimize my Firefox, I’d prefer it to really get out of my way, taskbar and all. This handy extension sends it to my notification area, requiring just a double click to bring it back.
MozAmPeek Streamer
Occasionally I come across links to mp3 or ogg etc. files, and would rather not have to go through the trouble or wait of downloading them first to listen to them. Usually to avoid this, I would copy the file’s URL. open up Winamp, get the Open URL dialog, paste it in and go to stream it instead. Quite tedious, possibly moreso than simply downloading. This is where MozAmPeek streamer comes in. This handy extension adds an option to the download dialog when you’re downloading a configured extension to simply do it all for you. You can configure multiple file types and players.
NoScript
NoScript is pretty much a condom for firefox, blocking all potentially unsafe Javascript. It works on a pre-emptive basis, meaning that initially it’ll probably annoy you until you’ve gone through the task of whitelisting all of your visited sites, though once you’ve waded through that, protects against unknown attacks.
NoScript is a so-so for me, if I didn’t already have it and knew how it worked I probably wouldn’t re-install it, but I keep it handy. It does turn out useful when browsing zealous sites that try to block my right click menu or stop be copying their text.
Save Complete
Anybody familiar with Firefox’s built in “Save Page As…” function is probably aware of how broken it is. This fetches everything required for the page, including all stylesheets and images set in those stylesheets.
Screen grab!
Screengrab is a cool window snapshot tool. It’ll save a selection, visible portion, or the entire page as either a PNG or JPG image.
SearchStatus
Privacy Zealots will probably want to avoid this one, since it emulates Alexa’s toolbar reporting. I use it to display a handy pagerank meter in my status bar, along with quick tools to check a domain’s WHOIS, robots.txt, and other neat stuff. I disabled the compete rank as well as the Alexa rank, since Alexa is a flawed system anyway.
Tab Mix Plus
If you’re like me and sometimes find yourself with as much as 50+ tabs open sometimes, Tab Mix Plus is a lifesaver. It allows a silly amount of customisation and precision along with features. I can drag tabs around, give or switch focus, pull one tab from one Firefox window and drop it into another, Auto-reload a particular group of tabs, close a selection, the list goes on.
Tab Scope
Tab Scope provides a real-time and live preview of the contents of other tabs when they’re hovered over. You can even use the contents of the other tab without actually switching to it.
Tiny Menu
Another tool in my quest to minimalize firefox, Tiny Menu lets me compact the normal row of menu options into a single button. I leave my Bookmarks entry out of it, since I use that frequently.
Titlebar Tweaks
Tidy up, remove, or just replace with something silly the titlebar text of your Firefox window.
Web Developer
It’s hard to figure out where to start with this. This tool is simply a must-have for anyone into web design or HTML, CSS and the like. Useful for debugging or figuring out your own work, or for simply snooping on other sites’ markup. I use its many features frequently when working on a design, and now couldn’t live without it.
X-Ray
X-Ray adds a context menu option that lets you transform a page into a version with visible tags. See the screenshot for an idea of what I mean. It’s useful for a quick snoop at a page’s source without going through the trouble of opening it’s source code.
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