SolutionBase: Finding the hidden bells and whistles in Firefox

by Derek C. Schauland | May 16, 2007 3:14:00 PM

Tags: Web browsers, Derek C. Schauland, Mozilla Firefox

Takeaway: Firefox 2.0 is a very popular browser, but there's more to it than what meets the eye. Derek Schauland shows you what you can find behind the scenes by giving a brief look at Firefox's about: pages.

This article is also available as a TechRepublic download.

Mozilla Firefox, now in release 2.0, has made huge advancements in Web browsing. Tabbed browsing and anti-phishing protection are its most visible improvements. Other features can be added into the browser through extensions, making this browser do more of users' bidding.

These features are great and certainly make this a favorite browser, but what if there were more? There are additional features hidden beneath Firefox's exterior waiting for you to discover. This article will look at all but one of the hidden items within Mozilla Firefox; the last feature will be looked at separately, as it has the most impact on overall experience when used. I will be covering that page in depth in a later article.

What's 'missing’

The hidden pages of Firefox are configuration items that allow and end users to see and make changes to the way Firefox operates. I will refer to them as the about: pages. They are available through the about: operator. You can see the pages by typing the following commands in the Address field:

• about: Shown in Figure A, this page will show the about information for the Firefox application. Similar to the usual Help → About menu option found in most applications (and in Firefox, too).
• about:buildconfig: Displays platform configuration information used in the running build of Firefox.
• about:cache: Shows the caching information stored for Firefox.
• about:plugins: Displays the installed plug-ins running within the current install of Firefox.
• about:credits: Shows the brains, and the coding brawn behind the Firefox project.
• about:Mozilla: Displays quotations from the Book of Mozilla.

Figure A

The about: page and a portion of the page text it displays.

We’ll look at each of these items throughout this article; learn when you might wish to make use of these hidden gems, and how to access them within Firefox.

How the about: page works

Notice that the address bar shown above has about: as the page address. This includes the : as part of the word. This is how Firefox knows that the page is browser-internal. Simply typing about in the address bar should treat about as a keyword and take you to http://www.about.com, which will not allow you to play with your Firefox installation. All of the remaining pages we visit for this article will begin with about:.

The about: page, which also gets displayed in the usual menu fashion (Help → About), doesn't present a huge amount of customizable opportunity, but it may be a handy page to remember if you find yourself searching for the version (when chasing after extensions) to check compatibility. Since [Ctrl][L] puts your cursor in the address bar with the current address highlighted, this is a much faster alternative for the keyboardists out there.

about:Mozilla

One of the hidden pages that is there more for show is the about:Mozilla page. It contains a verse from the Book of Mozilla and displays this verse for all to see. To access the Book of Mozilla, simply enter about:Mozilla into the address bar. You should see something similar to Figure B on the next page.

Figure B

The Book of Mozilla, shown in the hidden about: pages.

about:credits

Another showy page within the Mozilla Firefox browser is the credits page. This page presents a list of those who have contributed to the development of the code, from initial builds all the way through the current release of the browser. If you want to know who has worked on the Mozilla project, this is the place to go.

You cannot e-mail any of the contributors; but, at the foot of the page, it does provide a way to suggest developers for addition to the list. Also, the contributors listed worked on coding, quality assurance, or documentation. To access the credits page, enter about:credits in the Firefox address bar, as shown in Figure C.

Figure C

Entering about:credits will display a list of contributors to the Firefox project.

about:buildconfig

This page shows the current platform configuration and parameter information of your current installation of Mozilla Firefox. This might be useful to those developing plug-ins or extensions for the browser. This page is display only. Figure D shows an example of what you might see here.

Figure D

Theabout:buildconfig page shows instance platform and configuration arguments used by Firefox.

about:plugins

One of the most popular features of the Mozilla Firefox browser is its extensibility. You can add plug-ins to any installation of Firefox to customize your Web browsing experience. There is an entire directory of plug-ins available at http://addons.mozilla.org, as well as some third-party items. Plug-in installation is as simple as pressing the Install Now button on the page for the add-on; and, when prompted, telling Firefox to install the plug-in. When it has finished, you will be prompted that the extension will be available the next time you start Firefox.

Once you have started loading all these extensions, you might wish to find out which add-ons are installed within the browser and which of those are enabled or disabled. The about:plugins page will list all of the plug-ins detected on your system, provide information about them, and list their status.

For each plug-in, the page will display its MIME Type, description, any suffixes it supports (think file extensions), and whether it is currently turned on. Figure E below shows the management window, the page you might see when looking to list plug-ins. All of the plug-ins can be managed from the Tools menu within Firefox.

Figure E

Theabout:plugins page shows installed plug-ins within Firefox.

To manage the plug-ins for a current installation of the browser, navigate to Tools | Add-ons. You will see something similar to Figure F below.

Figure F

Extension management in Firefox.

about:cache

The last of the hidden pages I will discuss in this article is about:cache. This internal page shows information about the browser cache including the number of entries, maximum cache size, current size and inactive storage. You can also click a link to list the entries in the cache.

This can be helpful in troubleshooting issues with page loads, or any general-usage issues seen in Firefox. Figure G shows the about:cache screen.

Figure G

Cache information used by Firefox.

about:config

Another hidden page within Mozilla Firefox --about:config -- will be covered in another article. This page allows you to modify configuration parameters used by Firefox to truly make it your own. Some very interesting tweaks can be made here; and, due to the number of items available, it would be best covered on its own.

That's about:it

The about: pages covered here are a good starting point for easter-egg items hidden within Firefox; surely there will be a good amount of use (and great plug-ins) that come from the availability of these pages. Most of the about: pages don’t do much, but at least you can find out some interesting things about your browser once you start looking behind the scenes.