Four great add-ons/extensions extend Firefox functionality and save you a lot of time.

I know, I know. I promised to give you Part II of the frame-crossing TechTip, but time has been short, and I haven't finished it yet. But I will do it soon. Meanwhile, I'll present you with four add-ons for Firefox.

First of all, I am not religious about either IE or Firefox. I use both browsers, and I am not saying that IE sucks and that Firefox is the one and only, but I am saying that if you develop Web applications, Firefox is in my opinion better that IE. And if you include a few add-ons, it just becomes superior. And Firefox is open source, so you can just download and install it, and you're ready to go.

What Are Firefox Add-Ons?

Firefox add-ons are small pieces of codes that somebody has written and uploaded for the rest of us to use. They can contain a wealth of functionality, or they can do just one simple thing. There are thousands of them, and the four I will focus might be found in other versions that might function differently. All I can say is this: Install, test, and use them. If you don't like them, uninstall and find something new.

Before we dive into the add-on sea, please understand that I cannot cover all the functions of the ones I'll present, so I'll just show you small examples of what they can be used for.

There are serval ways to get to the Web site where all the add-ons are located. I launch Firefox and select Tools > Add-Ons. You'll see a picture like the one below:

Figure 1: Get a list of the Firefox add-ons. (Click images to enlarge.)

Click on Get Extensions. This will take you to Mozilla's Firefox Add-ons: Browse Extensions by Category. You can now start searching for add-ons, and I can tell you that there are many clever people in the world who have invented all kinds of add-ons. The only limit is your imagination.

Here comes my first choice:

Firebug by Joe Hewitt

This is a great tool that lets you debug, edit, and monitor your code right on the screen. When you activate it, the browser window splits in two, giving you a working area in the bottom of the screen.

Use it when you get a nagging JavaScript error. Firebug will locate it in seconds. If you have trouble getting an overview of some complicated CSS, it will show all the "connections." One powerful feature is the inspect option. Click it and move your mouse over the screen and you see the code associated with the HTML section you point at. See Figure 2.

Figure 2: Firebug lets you debug, edit, and monitor your code.

You can download Firebug here. It has its own Web site where you can find documentation and any help you might need.

Web Developer by Chris Pederick

The name almost says it all. After you have installed it, you'll get a nice toolbar with all the Web developer tools you never knew you were missing. See Figure 3.

Figure 3: Web Developer's toolbar has all the tools you need!

The toolbar is divided into different options, like Cookies, CSS, Forms, and so on. For example, suppose you have a Web page that requires entering a password. You select Forms > Show Passwords, and a warning will appear. Accept it, and the stars will vanish and the password will be displayed. You can also see all the names used in a form, display the size of the images used on a page, or show the path of the images. Web Developer contains a lot of functions that you might never use, but isn't it nice to know that they are there anyway?

You can download and install Web Developer from here. 

Cooliris Previews by the Cooliris Team

The first two add-ons were programming add-ons. The next one is very useful for surfing the 'net.

I read news every day, and I always dislike it when I have to click on an article, read it, and then remember to press the Back button to get back to the previous page. Cooliris solves this problem. It will add a little icon to every link, which will be shown when you move the mouse over it. Instead of clicking the link itself, just move your mouse over the icon and a window will open to show you the content behind the link. You can "park" the link in a temporary Cooliris stack, email it, or do several other things with it. It will also mark a link as "visited," which is helpful when you are on a page with many links.

You can download and install Cooliris from here.

And while you're at it, take a look at PicLens, also by the Cooliris folks. PicLens supports sites like Facebook and Google Images. It shows all the pictures on a "picture wall." Very cool!

Tab Mix Plus by CPU, onemen

This add-on will enhance the use of Firefox's tabs. You will be able to change the color of the tab while it is loading, duplicate a tab, control how focus should be when opening a new tab, etc. Have a look a Figure 4, which
will you an idea of how many options you have with this add-on.

Figure 4: Tab Mix lets you manage Firefox tabs.

And So Much More...

Well, that's about it for this time. This TechTip has only scratched the surface of this wonderful sea of tools, but I hope it will start a lot of talk in the forums, where people will share their own favorite add-ons with each other.

And I promise I'll be back very soon with Part II of the frame-crossing tip.

Until then, add on and join the fun.

Jan Jorgensen is one of the owners of www.reeft.dk, which specializes in mobile and i5 solutions. He works with RPG, HTML, JavaScript, Perl, and PHP. You can reach him at This email address is being protected from spambots. You need JavaScript enabled to view it..