Following the release of Firefox 41 just yesterday, Mozilla today updated the beta version of its browser to version 42 for Windows, Mac, Linux, and Android. This is a massive release, as Mozilla wants its users to test a slew of features, including its new experimental private browsing mode with tracking protection.

The new private browsing mode goes further than just not saving your browsing history (read: porn sites) — the added tracking protection means Firefox also blocks online services that could track you while you’re surfing the web, and it works on all four platforms. The feature is almost like a built-in ad blocker, though it’s probably closer to browser add-ons like Ghostery and Privacy Badger¬†because ads that don’t track you are allowed through.

Here is Mozilla’s thinking behind the feature:

Our hypothesis is that when you open a Private Browsing window in Firefox you’re sending a signal that you want more control over your privacy than current private browsing experiences actually provide. The experimental Private Browsing enhancements ready for testing today actively block website elements that could be used to record user behavior across sites. This includes elements like content, analytics, social and other services that might be collecting data without your knowledge.

The new private browsing mode also has a Control Center with all of Firefox’s site security and privacy controls. To try it out, click the hamburger menu button (three lines in the top right corner), click the New Private Window icon to launch a Private Browsing session, and you’ll see a screen that confirms Tracking Protection is on. Now all you have to do is browse the Web as usual.

3TP

That’s for desktop browsers. On Android, tap the Firefox Menu button (below the screen on some devices, or at the top-right corner of the browser on others) and then tap New Private Tab.

In short, Mozilla is attempting to take browser privacy to the next level. The company is seeing a lot of support from Firefox users, especially those who believed private browsing was already protecting them from third-party tracking on the Internet.

There are also potential performance improvements. A recent paper found that with tracking protection enabled, the top 200 news sites saw a 44 percent median reduction in page load time and 39 percent reduction in data usage.

In August, Mozilla added the new experimental feature to Firefox Developer Edition for Windows, Mac, and Linux, as well as the Firefox Aurora channel on Android. Now it’s arrived in the beta channel, though Mozilla didn’t say when it expects it to arrive in the stable channel.

Desktop

The other big highlight in Firefox for Windows, Mac, and Linux is the addition of tab audio indicators. We broke the news in July that the feature was coming to Firefox, it came to Firefox Nightly later in the month, and now it’s finally available for beta users.

The feature shows a speaker icon if a tab is producing sound. A single click mutes (speaker icon gets crossed out) or unmutes the given tab. Here is a tab audio indicator and muting in action:

firefox_nightly_mute

The best part is that you can mute a tab without having to switch to it first. As shown in the screenshot above, I was able to click on the speaker icon to mute the YouTube tab without leaving the VentureBeat tab.

This functionality has been available as browser add-ons and extensions for a while, but users want it built into the browser. While Chrome has had audio indicators for more than a year now, it still doesn’t let you easily mute tabs. The option is available in Google’s browser, but it’s not enabled by default (you have to turn on the #enable-tab-audio-muting flag in chrome://flags/).

Here is the full Firefox 42 beta changelog:

  • New: Private Browsing with Tracking Protection blocks certain Web elements that could be used to record your behavior across sites
  • New: GTK3 integration (GNU/Linux only)
  • New: Indicator added to tabs that play audio with one-click muting (Adobe Flash supported since version 19)
  • New: Login Manager improvements: Improved heuristics to save usernames and passwords, edit and show all logins in line, Copy/Paste usernames/passwords from the Context menu, migration imports your passwords to Firefox from Windows Chrome and IE; import anytime from the Login Manager
  • New: Control Center that contains site security and privacy controls
  • New: WebRTC improvements: IPV6 support, preferences for controlling ICE candidate generation and IP exposure, Hooks for extensions to allow/deny createOffer/Answer, improved ability for applications to monitor and control which devices are used in getUserMedia
  • Changed: Improved performance on interactive websites that trigger a lot of restyles
  • HTML5: Implemented ES6 Reflect
  • HTML5: Support ImageBitmap and createImageBitmap()
  • HTML5: Ship Push messaging with disabled web notifications from ServiceWorkers
  • Developer: Remote website debugging over Wi-Fi (no USB cable or ADB needed)
  • Developer: Asynchronous call stacks now allow web developers to follow the code flow through setTimeout, DOM event handlers, and Promise handlers.
  • Developer: Configurable Firefox OS Simulator in WebIDE, to simulate reference devices like phones, tablets, even TVs
  • Developer: CSS filter presets in the Inspector
  • Developer: Ability to save filter presets inside CSS Filter Tooltip

As always, there are lots of changes developers should take a closer look at.

Android

While Firefox 42 beta is a bigger release on the desktop, the Android app is still getting some notable improvements. Aside from the new private browsing and tracking protection, the biggest one is probably being able to open links from Android apps in the background.

Here is the full Firefox 42 beta for Android changelog:

  • New: Private Browsing with Tracking Protection blocks certain Web elements that could be used to record your behavior across sites
  • New: Open external URLs from Android apps in the background
  • New: Family-friendly browsing support for Android restricted profiles
  • New: about:logins now lists all saved logins, and allows users to view/edit or delete logins
  • New: Support direct voice input from the URL bar
  • New: Open multiple links without switching apps
  • New: Use “scrollable tabs” for panels navigation
  • Changed: Improved performance on interactive websites that trigger a lot of restyles
  • HTML5: Implemented ES6 Reflect
  • HTML5: Support ImageBitmap and createImageBitmap()
  • Developer: Remote website debugging over Wi-Fi (no USB cable or ADB needed)

Mozilla is planning to release Firefox 42 at the start of November, though not all of these features will make the cut.

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