Mozilla today launched Firefox 45 for Windows, Mac, Linux, and Android. The browser has gained a new Firefox Hello feature called tab sharing but has lost another one: Tab Groups.

Firefox 45 for the desktop is available for download now on Firefox.com, and all existing users should be able to upgrade to it automatically. As always, the Android version is trickling out slowly on Google Play.

Mozilla doesn’t break out the exact numbers for Firefox, though the company does say “half a billion people around the world” use the browser. In other words, it’s a major platform that web developers target — even in a world increasingly dominated by mobile apps.

Desktop

The biggest highlight in this release is that you can now instantly share tabs when you start a Hello conversation in Firefox. When you click the Firefox Hello icon and invite someone to chat, Hello will now instantly share the tab you’re viewing with them when they join.

With Firefox 44, Mozilla launched an experimental WebRTC feature that let users make free voice and video calls without needing to download additional software or plugins, nor create an account. Powered by the OpenTok real-time communications platform from TokBox, owned by Spanish carrier Telefonica, Mozilla calls Firefox Hello “the first global communications system built directly into a browser.” Because WebRTC is compatible with Chrome and Opera browsers as well, you don’t need the same software or hardware as the person you want to call.

While one tab feature has been added, another has been removed. Mozilla says Tab Groups (also known as Panorama) weren’t used “very much” and so it dropped the feature from Firefox for Windows, Mac, and Linux.

As the name of the feature implies, Tab Groups let you visually organize related tabs into groups. You could then switch between groups and quickly search through all of your tabs.

When you update to Firefox 45, you will see a special tab explaining what has happened. Your existing Tab Groups will be bookmarked automatically (as shown below) and you will be able to access them by clicking the Bookmarks button in the toolbar.

You’ll also be able to restore background groups into separate windows. Firefox will also make a one-time backup of your Tab Groups data, stored in your profile folder, so add-ons recreate your Tab Groups.

Indeed, Mozilla is pointing users to add-ons as a replacement for the missing feature. Specifically, the company recommends the Tab Groups add-on, which was created directly from the Firefox code and works just like the built-in feature did. “It will be as if the feature was not removed from Firefox,” Mozilla claims. Other recommended add-ons include OneTab and Tree Style Tab.

Here’s the full Firefox 45 changelog:

• Instant browser tab sharing through Hello
• Tabs synced via Firefox Accounts from other devices are now shown in dropdown area of Awesome Bar when searching
• Synced Tabs button in button bar
• Introduce a new preference (network.dns.blockDotOnion) to allow blocking .onion at the DNS level
• Guarani [gn] locale added
• URLs containing a Unicode-format Internationalized Domain Name (IDN) are now properly redirected
• Various security fixes
• Tab Groups (Panorama) feature removed
• Ability to filter snapshot output in memory tool
• Fine tune animations by changing the playback rate of animations in the animation-inspector’s timeline
• DOMContentLoaded and load events shown in the network monitor timeline
• Added Negative url filtering for the network monitor
• Support for diffing heap snapshots added to the memory tool
• Inspector search now matches results from all content in the page, including subframes
• List of animated properties and keyframes is now displayed when clicking on an animation in the animation-inspector’s timeline
• Push API support, part of Progressive Web Applications
• Support delivery of a Content Security Policy (CSP) via a meta tag
• Web Speech synthesis API
• ES6 Classes

If you’re a web developer, more details are available for you here: Firefox 45 for developers.

Android

Firefox 45 also drops support for Android Honeycomb (versions 3.0 through 3.2.6). Mozilla also plans to end support for Android Gingerbread (versions 2.3 through 2.3.7) next.

The Android 3.0 change will go into effect next month. To be clear, Firefox will still work on Android Honeycomb devices, but they will no longer receive automatic updates or support for Firefox. In other words, Firefox 45 is the last version for Android Honeycomb.

Old Android versions aside, Firefox 45 adds a few small improvements and changes. There’s now an option to choose with images to download while browsing (for bandwidth saving), and some settings have been moved around.

Here’s the full Firefox 45 for Android changelog:

• Click-to-view Images option in the menu’s advanced settings lets users choose which images on the Web they download to conserve data usage
• Provide system notification to give an End Of Life message to Android Honeycomb users
• Add toggle to disable sharing of camera and microphone in admin UI for family friendly browsing
• Introduce a new preference (network.dns.blockDotOnion) to allow blocking .onion at the DNS level
• URLs containing a Unicode-format Internationalized Domain Name (IDN) are now properly redirected
• Various security fixes
• Disable the inclusion of the URL when sharing selected text from web page
• Optimized & re-organized app Settings
• Replace super toasts with snackbar
• Simplified admin UI for family-friendly browsing on tablet in restricted profile
• ES6 Classes
• Support delivery of a Content Security Policy (CSP) via a meta tag

Mozilla releases new Firefox versions every six to eight weeks, and we thus expect Firefox 46 to arrive by the end of April.

VentureBeat