Now at version 48, Firefox's biggest change since my last review is to relegate Flash content to on-demand status. It's the boldest move away from the deprecated Web technology by any desktop browser. Of course, many other improvements have also made their way in, including process separation, enhanced download protection, and a 64-bit version. Firefox continues its trend of being the most privacy-concerned and customizable Web browser. Other unique features include tracking protection in Private Browsing mode, Hello video chat, an ad-free Reading mode, and a social-sharing tool. It's also fast and makes frugal use of RAM. In features and customizability, Firefox is unmatched, making it our Editors' Choice for Windows Web browsers.

Starting Up

Firefox is available for Mac and Linux, as well as Windows 10, ($139.00 at Microsoft Store) 8, 7, Vista, and XP (though we don't recommend you run the last two). If you're already a Firefox user, all you have to do is restart the browser to get the new version (you can also go to Help > About Firefox to force an update). A fresh install of the browser took up just 91MB compared with Google Chrome's 406MB. You can import bookmarks from any other installed browsers on first run, and the setup is as easy as it gets. You can also choose any search provider you like, though Yahoo is the default.

A Slick Look

Firefox's has the best-looking browser interface around. The new look resembles that of Chrome, but there are real differences. Chrome's tabs aren't rounded, and they don't recede into the window border color when they don't have the focus, as Firefox's do. Chrome also displays all tabs no matter how many you have open, which makes them impossible to identify when you have a lot. With Firefox, the tabs remain readable since you scroll back and forth by clicking an arrow when you have too many to read open.

Firefox also keeps the Search box separate from its Address box. This is important privacy protection, as browsers that use a single box typically send everything you type there to a search provider. Firefox's search box includes a dropdown arrow that lets you choose among search providers. This is handy if, for example, you know you want the Wikipedia or eBay result. It also prevents search entries from being interpreted as Web addresses. For example, if you want to search for content about asm.js (a subset of JavaScript), the address box tries to open a page, while the search box turns up links about the asm.js spec and so on.

Firefox's New Tab page features tiles for your most frequently visited sites and a search box. I do, however, miss Internet Explorer's Recently Closed tabs choice on this page. Granted, the Firefox default Start page does offer this option, along with big buttons for downloads, bookmarks, and settings. If you just want a blank new tab, the grid button at top right grants your wish. Chrome's New Tab page annoyingly doesn't let you choose the site tiles as all the other browsers do, but does let you delete tiles it's selected. The main thrust of Chrome's New Tab pages is to push you towards Google's online services.

As in many modern apps, Firefox's main menu now sports the three-dash (aka hamburger) button. When clicked, this drops down not a standard text menu, but rather a panel of icons for settings, add-ons, and more. It's very clean and less overwhelming than the multiple unfolding text menus found in previous versions (and still found in Chrome).

Keeping with the Firefox tradition of customizability, an always-present choice at the bottom of this panel is Customize, which switches the browser to a mode that lets you change any of its buttons in either the panel itself or in the toolbar next to the search bar. One customization offered by newcomer browser Vivaldi but not found in Firefox is tab tiling, which lets you see more than one site in the main browser window.

You can eliminate the browser's top title bar for the tabs-on-top look, or toggle standard text-based menu options and the bookmarks bar.

Firefox's bookmarking tool is a welcome convenience. Its double button consists of star and clipboard icons. When you tap the star, an adorable animation flies it over to the clipboard, and the star turns blue, showing that the current site has been added to your bookmarks. Tapping the Clipboard button opens a drop-down menu that displays all your recent bookmarks.

You can also summon a full bookmark sidebar or separate window for a view of your bookmarks. The History button offers a sidebar, too, though its button isn't in the toolbar by default. Both the Bookmarks and History sections include search bars. Microsoft Edge's combined Favorites and History button makes for a clean interface. In Chrome, you have to go through menus to get to either.

Better Syncing

Firefox's syncing capabilities not only let you see your bookmarks and settings in any instance of the browser on any device, but also even let you continue a browsing session from machine to machine. You can sync passwords, extensions, and form data, as well. The new syncing method is much easier to set up. Before, you had to enter a generated code in any new device. Now you simply sign in. The synced information is encrypted end to end, according to Mozilla.

Firefox syncing now extends to both its Android and iOS mobile apps. You can also sync Firefox with the excellent Mercury browser app. Windows Phone users can look to the third-party Firesync app.

Firefox includes a button for the Pocket Web bookmarking service. You can use the same login you do for Firefox's own syncing for this feature, which offers an amazingly simple way to save a webpage. Just click the toolbar icon, and it's available either on synced browsers or in Pocket's Pinterest-like display of your saved sites. One online tool you won't see in Firefox, however, is an equivalent to Maxthon Cloud Browser's and Vivaldi's own online note-syncing services.

Tracking Protection in Private Browsing

Firefox's Private Browsing mode doesn't save logins, history, site cookies, or cached pages for private sessions—it's just like you were never there. But unique among browsers is that it offers tracking protection while you're browsing privately. With this change, online Web trackers don't see your browsing activity. If you've ever installed a tracking-protection extension such as Privacy Badger, you know what a surprising number of sites track and store your browsing activity. I've long thought that every browser's privacy features should include this sort of protection.

Firefox Hello

Skype, watch out! With Firefox's built-in Hello video chatting (with the cooperation of Telefonica, a Spanish communications provider), you no longer need to install separate software to chat. You don't even have to create a separate account to start seeing your far-off friends. To get started with Hello, you click the smiley face button on the left side of the browser toolbar, and then press the Start a Conversation button. This opens a chat box at the bottom of the browser window, showing your own webcam image.

You can conduct multiple conversations at once, and you can turn off your camera, mute your mic, or share your browser tabs or other windows on your computer with your chat partner. One cool thing is that, as with Skype, when you enter a conversation, your other audio is turned way down so you can hear, and there are clever sound effects to clue you in when someone joins or leaves a chat and enters a message.

One problem, though, is that, unlike in Skype, Firefox offers no way to switch from the back to the front camera. Also unlike Skype and Hangouts, Hello limits you to one-to-one conversations—no group calling. But video and sound were acceptable if not perfect (which is to say, par for the course in video chat) in my Hello test conversation.

Reading Mode

These days, a lot of sites, particularly magazine- and news-type sites, have become nearly unreadable with the number of pop-up ads and auto-play videos they foist on you. Even formerly staid publications like the New York Times are now sometimes cluttered beyond readability. A Reading mode has become a necessity, and after Apple's Safari led the way several years ago, Firefox now offers such a tool. Microsoft's Edge browser also offers a Reading mode. Chrome doesn't include this feature, which may not be surprising given Google's ad-serving business.

When you land on an article page, an icon showing a book appears in the right side of the address box. You click it to turn on Reading mode. Firefox offers some formatting choices from an easily accessible right-hand sidebar. You can choose an off-white paper, bright white, or black background, and there are nine font sizes with serif and sans-serif options. One thing I prefer about the Reading modes in Safari and Microsoft Edge is that you can still see inline images with those. But Firefox has an advantage: Its Reading mode works for all sites, whereas Edge and Safari let publishers opt out.

Social: Firefox Share

These days, no browser should be without a persistent Share button. After all, what do we do on the Web now besides finding sites that amuse us and sharing them to Facebook, Twitter, Tumblr, LinkedIn, and the rest? Firefox's Share button, which cleverly looks like a paper airplane, lets you share to these services as well as to email. It's also extensible to any new online sharing targets that may come along. It's not in the toolbar by default, so you have to drag Share This Page there from the Customize view. Once you do this, you can choose which sharing targets to include.

Tab Tools

Firefox's unique Panorama feature, offering a revolutionary way to organize tab groups, is no longer a built-in browser feature. It's now available as an extension called Tab Groups. This a nifty feature lets you drag tabs among boxes that you can resize and reposition. You can even give a name to a tab group to keep it organized.

If there are sites you always want access to, you can pin their tabs to the left side of the Tab bar—just as you can in Chrome and Edge. These pinned tabs appear narrower, showing just the site icon. The pinned sites also load automatically when you start Firefox. You can also create a shortcut icon on your desktop for a site by dragging its information icon. And, as with all browsers these day, you can drag tabs side-to-side to reposition them, and outside of the browser to create new windows.

Standards and Code Support

Mozilla and Firefox have long been at the forefront of Web technology innovation. The latest version not only supports the lion's share of HTML5 features, but also other emerging standards such as WebRTC, which enables the Hello video-chat feature discussed above. Another technology Mozilla has led is Emscripten and asm.js, which allow native-code performance for processing-intensive Web apps such as 3D gaming. Microsoft is moving ahead with including this capability in a future release of Edge. It's a more open version of Google's Chrome-only Native Client technology.

All of this native Web support means that Firefox plug-ins such as that for Adobe Flash aren't really needed, and can cause more security vulnerabilites than they're worth. In fact, Mozilla has stated that it intends to "remove support for most NPAPI plugins in Firefox by the end of 2016." NPAPI is the plug-in specification introduced back in the days of Netscape (it's short for Netscape API).

Firefox supports Web Audio API, along with more than 30 other Web APIs, many of which were prompted by Mozilla's ill-fated Firefox OS mobile platform initiative. Many, such as mouse-lock and geolocation APIs, apply to desktop browsing, too. The browser also supports the faster HTTP/2 replacement for HTTP, the basic networking communications protocol of the Web. You can see which companies have implemented which features in this table.

Some of Firefox's capabilities are not included on Niels Leenheer's HTML5Test website (see the performance table), which tests for its own set of emerging standards and W3C HTML5 recommended ones. Another reason the test should be taken with a grain of salt is that it doesn't actually test whether the functions are correctly implemented, just that the browser acknowledges that the function is recognized.

Performance

Firefox has come a long way in terms of speed, as has the browser field in general. Chrome once had a speed advantage, with blazing JavaScript rendering, that advantage has mostly vanished. In particular, Windows 10's Edge browser beats it in most speed tests I run (see table), while Firefox tops a few.

Performance is most easily and repeatably measured by JavaScript benchmarks. But browser performance involves more than just what shows up on these synthetic JavaScript benchmarks, since loading webpages isn't just about JavaScript. HTML and CSS parsing, network interaction, prioritization of which content is loaded first, handling mouse moves, painting the window with content, and caching strategies all play roles. I no longer test startup speed, since all of the browsers I consider start up snappily, usually in under 3 seconds.

I tested on a Surface Pro 4 ($779.49 at Amazon) with a Core i5-6300U CPU and 8GB RAM, clearing all browser's caches, quitting all other apps, and removing all extensions. I kept the tablet PC plugged in and ran each test five times, threw out the highest and lowest results and averaged the rest.

JavaScript Benchmarks. SunSpider, formerly the best-known JavaScript benchmark, has been superseded by JetStream, which combines routines of the former SunSpider with others from LLVM and Apache. Like Google's Octane benchmark, which I also use, JetStream is designed to be more real-world, so it takes longer to run, cycling through 39 tasks three times. A higher score is better on both of these tests.

I recently added the WebXPRT benchmark to my testing. This includes six tests that its maker, Principled Technologies, claims mirror real-world Web application use. Using JavaScript and HMTL5, it tests the following set of tasks: Photo Enhancement, Organize Album, Stock Option Pricing, Local Notes, Sales Graphs, and Explore DNA Sequencing. Firefox takes the crown in this one, in which a higher score is better.

Graphics Hardware Acceleration. Microsoft has published a series of benchmarks to demonstrate how use of a PC's graphics processor can accelerate some webpage-rendering tasks on its Test Drive site. I use PenguinMark, since it produces a comparable score and tests a wide variety of capabilities, including HTML5, JavaScript, CSS3, Canvas, WOFF (Web Open Font Format), and more. It also displays cute bundled penguins in the snow and plays my favorite Chipmunks Christmas song. On this test, Firefox used to perform extremely well, but now the Microsoft browser beats it handily. A higher score is better.

Unity WebGL Benchmark. WebGL allows game-level graphics inside a webpage, so I check performance of this with the Unity WebGL Benchmark. Unity WebGL is a great-looking benchmark that runs through visually demanding Mandelbrot sets, cryptography, and gaming physics scenarios, both 2D and 3D. One test is adorably named "Instantating[sic] and destroying a lot of Teddy bears." Edge and Firefox have a big lead over Chrome and Opera on this one—not surprising because the benchmark uses asm.js, which has better support in Firefox and Edge. A higher score is better on this benchmark.

Memory Use. I tested the browsers' RAM footprints by loading 10 media-rich websites into all the browsers at the same time and add up their processes' Memory entries in Task Manager. I had to make sure the sites actually loaded, because some browsers like to save you resources by not loading background tabs, Chrome and Opera in particular showed a lot of empty tabs when I first clicked on them. Of course, a lower MB number is preferable on this test. Firefox wins this, nearly halving Chrome's memory usage, while Edge trails by a surprising margin in this test.

Battery Drain. In light of all the controversy over Chrome draining laptop batteries, I ran PCMag's battery rundown test. I charged the battery fully, unplugged and played a song on SoundCloud in an endless loop, having connected the audio output to a plugged-in PC recording the sound in Audacity. The browsers were loaded with the same 10 media-heavy websites. I also kept the screen brightness at maximum, which helps account for the short time results I saw. The laptop I was using was an Acer Aspire E1-470P, whose battery was no great shakes to start with. The longer the battery could last on this, the better.

Firefox won, lasting 1 hour and 55 minutes. Chrome lasted just 1 hour and 18 minutes in my tests. The other browsers also got more life out of that poor old battery than Chrome. Opera lasted 1 hour and 36 minutes, and Edge lasted 1 hour and 32 minutes. For reference, with no browser running, the laptop's battery lasted 2 hours and 49 minutes. My methodology admittedly isn't quite perfect, since I don't simulate user interactions, but most of the sites loaded use auto-refresh to load new content, so that can be thought of as simulating active navigation. In any case, the results are so clear that I think they are worth reporting.

Developer Tools

Firefox arguably offers more for the Web developer than any other browser. In fact, there's even a Firefox Developer Edition of the browser. The Developer Toolbar offers a command line that can streamline a slew of Web developer actions. Accessible from the Web developer menu, the toolbar autocompletes any commands the developer starts to enter, and offers keyboard shortcuts to access the Web Console, Debugger, Style Editor, Cookie Editor, and more. It can even open extensions or snap screenshots of page elements.

Security

Firefox has long offered many security features, including phishing and malware protection, as well as integration with antivirus software. Firefox's support for standards lets sites make plug-ins even more secure. Content Security Policy (CSP), for example, lets sites prevent XSS (cross-site scripting) attacks, such as a commenter on a site executing scripts.

Firefox has also long been a leader in privacy, having introduced the Do Not Track system. There are now three choices: Do Not Track, Track, and Don't tell sites whether or not I wish to be tracked. The browser includes an API call that lets websites use JavaScript to check whether you've set this to indicate you don't want to be tracked. Unfortunately, the Mozilla answer relies on the ad networks to abide by your wishes—and many don't (most notably the largest of them all, Google). As I mentioned above, a good workaround for Firefox is to install Privacy Badger or something similar.

Burning Up the Browser World

Firefox is the best-looking browser around. It's clean, functional, and more customizable than the rest. Mozilla's browser also offers the best combination of performance, features, support for new Web standards, low memory usage, and privacy protections. All of this earns Firefox our Editors' Choice award for Web browsers for Windows.

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Further Reading