As Firefox's popularity has increased so has the interest in Firefox extensions or plugins. Two questions seem to surround this topic. The first is where do I find extensions for this web browser. The second is how do I download and install browser extensions. We'll answer both items.

One benefit the Firefox browser offers is the number of extensions developers have created. The number well exceeds a thousand. These extensions enhance the browser by adding features that weren't provided in the program. Some examples of additional functionality that extensions provide Firefox users:

• Create a desktop shortcut from a webpage address
• Open the same web page you're viewing in Internet Explorer
• Translate highlighted text on a web page into another language
• Add bookmarks to Del.icio.us
• Reopen a closed tab

Finding Firefox Extensions

While the above examples are but a small sampling, you can see more examples in various extension collections. The best known of these collections is maintained by the Mozilla foundation. The page can be accessed in two ways. The easiest method is using the Firefox browser and from the Tools menu, select Extension.

After you select Extensions from the menu, a new dialog (Figure 2) opens which lists any extensions already installed. At the bottom right, is a link to Get More Extensions.

The second way to get to the extension page is to navigate to the page by entering the URL.

Layout of the Firefox Extension Page

The main Firefox Add-ons page is organized into distinct sections as outlined in Figure 3.

(1) Across the top you have tabs representing different items you can add to Firefox. If you accessed Extensions from within Firefox, the Extensions tab is loaded. The other tab of interest is Plugins. Plugins are applications that allow your browser to view other content types such as Acrobat files, Macromedia flash files, etc.

(2) The Recently Uploaded section highlights existing extensions which have a newer version and their release date.

(3) The Top Extensions section lists extensions that have been downloaded the most from the Mozilla site. You might think of these as the tried and true bunch with lots of user comments. You can also see the number of downloads in parentheses. The numbers would not include downloads from other sources such as the developer's website.

(4) These two sections also provide RSS feeds if you want to follow the activity in your favorite reader or use Firefox's Live Bookmarks feature.

(5) The left section lists Categories. You might think of a category as a functional grouping. I find categories preferable to using the Search box in the top right if I don't know the name of an extension.

(6) In the top right, there is a search box where you can enter your terms. The advantage to using this box is you can locate extensions from multiple categories. It's also helpful to use this area if someone has provided you with the extension's name such as deskCut. When using search, the results are sorted by Last Update.

Each extension on the Mozilla site has a dedicated page. The page provides useful information such as author notes, viewer comments, viewer ratings, file size and screenshots. If the extension doesn't suit your needs, there is a subheading to the left called Find Similar Add-ons. Underneath you'll see category links that match the extension you're presently viewing.

Installing a Firefox Extension

The basic process of installing the extension is easy, but there are some nuances. Specifically, Firefox prefers installing extensions from Mozilla.org rather than a developer's site or another extension site. It considers these extensions safer and does not block the process.

Another minor safeguard appears when you click the Install Now link. When the Software Installation dialog first appears, there is a slight time delay before the Install button becomes enabled. This is to prevent you from accidentally clicking when you didn't mean to install the extension. The same delay happens if you were to move focus off of your browser by clicking another application. Clicking anywhere within the dialog, starts the countdown timer. The delay does not occur if you're updating an extension you've installed.

After you click the Install button, you'll see a dialog box similar to what you see when you selected Extensions from the Tools menu in Figure 2. The main difference is you're alerted to restart Firefox to complete the installation process.

Installing Extensions from non-Mozilla Sites

The installation process is similar except for the safeguard I mentioned earlier. In the example below, I started to install the extension directly from the del.icio.us site. One could argue that this is a trusted site since the publisher is releasing an extension that works on their pages.

Instead of immediately seeing the Software Installation dialog (Figure 5), I need to first deal with Firefox's message. To protect your computer, Firefox prevented del.icio.us from installing software on your computer.

To get around this safeguard, you need to click the Edit Options button that appears to the far right on the info bar. This will open an additional Allowed Sites dialog (Figure 8) where you must click the Allow button to accept the web site and then click the Close button. After you've allowed the site, you can proceed as before.

Once you start using Firefox extensions, you start looking for more as they do make your browsing experience better. It's almost an addiction. Like many additions, there can be problems if you have too much of a good thing. I find it's easier to install one extension at a time and see how it interacts with others. If you were to install multiple extensions on the same day, you might have a harder time determining which one might be causing any problems. The same rule applies to other software as well and not just extensions.

You'll also find people will blog or report about their favorite Firefox extensions. It's easy to do a search on any popular search engine with expressions like "favorite firefox extensions" or "best firefox extensions". This seems to be an area where a lot of people have opinions. Or, you could just use the Top Extensions or Popular category on the Mozilla page. Once you find your perfect plugin, you'll now know how to install it.

Referenced Firefox Resource

• Firefox Extensions Page
• How and When to Update Firefox
• Searching with Firefox Keywords