Firefox Tab Sharing
Last 8 March Mozilla 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.

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

With Firefox 34, 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, users don’t need the same software or hardware as the person they want to call.

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

As the name implies, Tab Groups lets users visually organize related tabs into groups. They could then switch between groups and quickly search through all of their tabs.

When users update to Firefox 45, they will see a special tab explaining what has happened. Their existing Tab Groups will be bookmarked automatically and they will be able to access them by clicking the Bookmarks button in the toolbar.