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Mozilla Extensions

By Robert Spotswood

Extending the Browser

In my last article (http://www.hal-pc.org/journal/2003/03_nov/Feature/mozilla/mozilla.html), I talked about some of the features that make Mozilla (http://www.mozilla.org) a better browser choice than Internet Explorer. However, Mozilla is more than just a web browser/mail client. It was designed from the ground up to be an application development platform. In fact, O'Reilly has published a book called "Creating Applications with Mozilla" (http://www.oreilly.com/catalog/mozilla)

One of the benefits of "development platform" design is that there are a number of add-ons, or extensions to Mozilla that allow it to do a number of different things, including changing how your browser works. If there is some feature you wish the browser had, chances are someone has written an extension for it.

When installing the extensions, many offer you a choice about where to install it. You can either install it in the main Mozilla directory, or in your local profile. If install it in the main directory, all users have access to the extension (assuming you have multiple users), but you will have to reinstall the extension when you upgrade Mozilla. If you install in your local profile, you can upgrade Mozilla without having to reinstall the extension, but only you have access to it. In either case, you will have to restart Mozilla (NOT your computer) after installation before you can start using the extension.

Adblock: Taming Flash Ads

Flash is a wonderful web plugin. It allows animation and even games if you have the plugin installed. Some sites require it for meaningful site navigation. But, more than a few sites abuse it, such as making you watch a short ego-trip about themselves before you enter the real site.

The worst abuse, though, is probably the various ads that are placed throughout the page you are reading or the ads in pop-up windows. A simple static image is one thing, but a flash ad, or more often, multiple flash ads, are down right annoying and can cause major motion sickness. If the ad is moving, it's probably Flash. Flash presentations aren't the smallest downloads in the world, which makes page loads take a lot longer for dial-up users on top of the other problems.

The pop-up ads are easily dealt with using Mozilla's built in pop-up blocker, but what about the ads embedded in the page you are looking at? How to deal with those? Using extensions, there are 3 ways to deal with them, the best of which IMHO is called adblock (http://adblock.mozdev.org/).

As the name suggests, adblock can be used to block ads from ever downloading. This saves bandwidth, and more importantly, prevents flash ads from playing, while, if setup properly, allowing other uses of flash to work fine. If you want to still "support" the sites you visit, adblock even allows the ads to be downloaded but hidden.

Adblock differs from the hosts trick (see http://pgl.yoyo.org/adservers/ for example) in three important ways. First, because you can use wildcards, or their much more powerful cousin, regular expressions, one line (called a filter) can block many different ads, even if the sources of the ads are different. It's easier to maintain than a hosts list. Second, you don't get a white box with an error message in it like you do with the hosts trick, but just a blank space. It is more pleasing to the eye. Finally, some sites serve ads from directories off the main server. The hosts trick can't block these ads, but adblock can.

Adblock can also import and export the filter list, so you don't have to create your own list from scratch. One list you can download is at http://www.spotswood-computer.net/adblock.html.

Diggler: Deceptively Useful

Figure 1: The diggler button
The diggler button

Another extension for Mozilla is diggler (http://diggler.mozdev.org/). It's tiny and the only change you see on the screen is a new symbol next to the location bar (see Figure 1). The main thing this little symbol does is it allows you to clear the location bar, and automatically puts the mouse cursor in the now empty bar space. No more click and drag if you want to type in a new URL or bookmark keyword. Doesn't sound like much, but once you get used to it, you will find it useful.

Linky: The Power to Handle Links

Linky (http://linky.mozdev.org/) is a little extension that makes opening all the links, or just all the image links, on a page easy. Some sites have lots of thumbnails (or links). The old way to see all of them is click on each one, wait for it to load, look at it, click the back button (or other window/tab close button), and repeat. Linky allows you to open all the links at once. You can even chose not to open some, such as already visited links. The links can be opened in either new windows or tabs (see http://www.hal-pc.org/journal/2003/03_nov/Feature/mozilla/mozilla.html if you don't know what tabs are).

Experience shows that even on dial-up, this is, overall, a time saver. Certainly it will help save some wear-and-tear on your mouse and wrist. Note that due to hotlinking issues, the "show all image links in one tab" option usually doesn't work in cases where it would be most useful. This is controlled by the webserver, not the browser.

Calendar: Schedule Your Life

While not actually a browser extension, the Mozilla calendar project (http://www.mozilla.org/projects/calendar/) is still quite useful. Some people live and die by their calendar. Well, Mozilla offers one too. It supports all the features you would expect: events, recurring events, alarms (including emailing alarms), and various views (day, week, month).

It uses the iCal standard for storing its calendar data, so you can share your calendar with any program that understands the iCal format. If you have access to an FTP or webdav enabled server, you can even use this to make your own calendar server. Also, there are a number of free calendars you can download (at http://www.icalshare.com/) to add to your calendar.

Googlebar: The Power to Search

The Googlebar project was created to address the widespread desire in the Mozilla community for the Google toolbar to support Netscape 7/Mozilla, since many users of Mozilla enjoy having all of Google's specialty searches in one convenient location. This is NOT an official toolbar from Google. However, according to the website (http://googlebar.mozdev.org/) the Mozilla toolbar supports some searches that the official toolbar does not.

Mouse gestures: Love It or Hate It

Mouse gestures is part of the Optimoz project (http://optimoz.mozdev.org/). This allows you to preform certain browser commands simply by making certain mouse movements. For instance, instead of clicking the back button (or ALT-left arrow), you could hold the left mouse button down and drag to the left anywhere on the screen to go back one page. This one of those things that some people love and some people hate.


The Mozilla Extension site has over 200 projects, although some are more complete than others. While I describe 6, I've only scratched the surface of what the Mozilla browser can do. Keep in mind, Mozilla also has a newsreader and email client component, and there are extensions for those as well. The best part is, all this is free! With Mozilla, you really can have the internet your way.