Review: Firefox 3.5 Makes Browsing Better

Mozilla's latest Web browser is a solid step forward, with features including private browsing, geolocation, and support for the latest audio, video, graphics, and HTML 5.

Firefox 3.5's private browsing mode lets you cover your tracks.
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Internet users are partying like it's the 90s, when the browser wars were roaring and Microsoft and Netscape were fighting to become the dominant window on the Web. These days, Microsoft Internet Explorer is in the lead -- just like then -- but we're also seeing an efflorescence of alternatives: Mozilla Firefox (which counts Netscape as an ancestor), Google Chrome, Apple Safari and Mobile Safari, and the venerable Opera.

Into the fray comes a new version: Firefox 3.5. This build offers significant improvements, including upgraded Web technology, geolocation, privacy tools, and tab management. The browser also improves performance over previous versions.

Private Browsing

Firefox 3.5 implements private browsing, catching up with features already available in Internet Explorer, Safari, Chrome, and Opera. When you're in private browsing mode, the browser switches off logging your history, cookies, user names, and passwords.

Even in private browsing, your Web traffic isn't guaranteed private. If your network manager is tracking your browsing on the server, private browsing does nothing to block that. Also, the servers you visit may be keeping records of your visit, especially if you log on to access the server.

Firefox's implementation of private browsing has a different user interface than competing browsers. The chief difference: When you switch to private browsing, Firefox shuts down all your existing browser windows and tabs, leaving only the private browser window open. Other browsers leave existing windows and tabs open and open a new window for private browsing.

I like the way Firefox closes non-private windows when in private browsing; I'm less likely to accidentally enter private information in a non-private window. However, other people might find it time consuming to switch back to non-private browsing, especially if they have a lot of open tabs and windows that need to be reloaded. It's a matter of personal preference.

If you forget to switch to private browsing before you visit a site, Firefox 3.5 lets you erase your tracks -- just go to the history menu, open "show all history," find the page you want to hide, and click "forget about this site." That's handy for those of us who are paranoid and absent-minded ("My enemies are conspiring against me -- but I can't remember who.") Geolocation

Firefox 3.5's geolocation feature can figure out where you're located.
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Firefox now knows where you are. Try it out on Google Maps: Click on the "Show My Location" icon on the top-left corner of the map, and Firefox will attempt to determine your location and -- with your permission -- let Google Maps know where you are.

Firefox uses the W3C Geolocation API, also supported by the Google Chrome 2.0 browser, and attempts to determine your location by looking around for nearby Wi-Fi access points and consulting a database of known Wi-Fi locations around the world; if that doesn't work, it looks up your IP address and finds your location using that information.

The first time I tried geolocation, I was in my company's Irvine, Calif., office, and Firefox determined my location pretty accurately. That's predictable; the company office is in a commercial Los Angeles suburb, in a crowded office building, in range of many Wi-Fi access points which are likely to have been in place a long time and accurately stored in geolocation providers' databases.

I tried it again at home in San Diego, and the geolocation was about six miles off. Again, that was predictable: I live in a suburban, residential neighborhood and the Wi-Fi access points around me change every few months. So my neighborhood may not be in the geolocation databases or, if it is, the data might be out of date.

Geolocation is a convenience, it'll keep you from having to type your address repeatedly when you're at home or in an office, and it'll be even more help if you're in a convention center or hotel and you don't know your address.

Performance Improvements

Firefox 3.5 speeds performance over previous versions, using a new JavaScript engine called TraceMonkey. JavaScript is the language used in Web 2.0 apps like Gmail, Google Maps, Zoho, and YouTube; TraceMonkey support means those apps will work faster than previously seen.

Firefox 3.5 handles crash management better than previous versions. Previously, when Firefox crashed and you re-started it, it asked you whether you wanted to re-open the tabs and windows from your previous session. Now, it asks you which tabs and windows you want to open, so you can exclude a misbehaving Web page to keep your browser from crashing yet again. Tab Management

Firefox 3.5 offers several new features for tab management.
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Firefox 3.5 features some nice tab-management features. Lift up a tab to move it to the left and right, and you get a semi-transparent thumbnail of the tab; very handy for absent-minded folks who can't remember which tab they were going to move.

You can move tabs between browser windows, which you could also do in previous versions of Firefox, but you can also drop a tab on the desktop to start a new window with that page. Tabs moved between windows no longer need to reload in the new location, which saves time.


The biggest improvement to Firefox 3.5 is something that isn't really visible to users just yet -- it supports the new HTML 5 standard for writing Web pages. HTML 5 is revolutionary, transforming the way we use the Web and making it possible to do things online that previously required a desktop application. All the major browsers support HTML 5 -- Firefox, Internet Explorer, Safari, and Opera -- although not always completely, in part because HTML 5 is still a work in progress.

HTML 5 allows applications to run offline, while disconnected from the Internet, storing data locally on the desktop or mobile device. It standardizes the offline capability previously available in Google Gears, which allows users to run apps like Google Reader, Gmail, Google Docs, Zoho, and Remember the Milk inside their browsers while disconnected from the Internet.

HTML 5 also supports several different technologies that will change the way Web pages look. It handles video and audio differently than the way we're used to seeing. You can embed video and audio into the HTML code directly, meaning you won't need to install a plug-in, like Adobe Flash, to play videos and audio files online on sites like YouTube and elsewhere. The video and audio will be more of an integral part of the page, not as much of a separate chunk as it is today.

Looking at the documentation for the video tag, you can see that it behaves pretty similarly to embedding images in Web pages. You can do some neat tricks with it that previously required sophisticated embedded Flash players (like the one available from YouTube). You can show controls on the video, optionally turn on autoplay, designate an image to display before the video starts, and designate the start time of a video.

After you crash, Firefox 3.5 lets you select which browser windows and tabs to re-open.
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Moreover, HTML 5 lets you do some wacky things with video. For example, check out this Mozilla demo video. The guy in the video is holding a light source in each hand. It's hard to tell for sure, but they look like iPhones with the screens set to display an all-white image. He's moving his hands in circles around each other. The page detects the moving light sources and displays a video in between them. The video-in-a-video turns and gets bigger and smaller as the light sources move around.

Support for CSS transforms makes it possible to rotate and skew page elements, simulating isometric 3-D rendering. This demo shows a rendering of a 3-D cube, with a playable video on one face and text and clickable buttons on other faces. Note: The demo link crashed Firefox 3.5 on Vista, although it worked correctly on a half-dozen other machines running different configurations of other operating systems.

This is wild stuff, and will soon make the Web much richer than it is today.

HTML 5 has more subtle enhancements. It supports native drawing of CSS drop shadows behind text and boxes. It also supports downloadable fonts, which means pages can display text with fonts that the viewer doesn't already have installed on the computer. SVG filters allow designers to apply blurring and other visual effects to most page elements.

HTML 5 will be huge in the long term, but Web designers first need to implement HTML5-compliant pages, so the changes aren't visible today.


I've been using Firefox 3.5 as my primary browser since it came out June 30, testing it on both the Mac and Windows, and have overall been pleased with its performance, stability, and features. Of course, as with any major upgrade, it has some bugs, rough edges, and incompatibilities. InformationWeek's parent company uses a service from Jive Software as its internal communications platform, and Firefox 3.5 does not seem to be compatible with the Jive service's WYSIWIG editor.

More significantly, I use the Mac password management software 1Password, and Firefox 3.5 seems to break 1Password's automated login.

Overall, however, I'm happy with the Firefox 3.5 upgrade.

The new version comes at an interesting time in the evolution of browsers, As this chart shows, over the past year, Internet Explorer has been steadily losing market share, even though it maintains a strong lead, while Firefox gains.

Opera, Safari, Chrome, and other browsers trail far behind Firefox, but they're gaining market share as well. With its new features and faster speed, Firefox 3.5 is a significant step forward in browser evolution, and will keep the new browser wars going on for another battle.

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