Firefox 4.0b2 released

July 29, 2010 · by Luke Ponio

Firefox 4 Beta 2 is now available for download. The beta update includes some of these new features from the previous Beta 1:

Firefox 4 Beta 2 is available in 24 languages.
Tabs are now on top by default on Windows and OSX - Linux will be changing when the theme has been modified to support the change.
You can turn any tab into an “App Tab” by right-clicking on it and selecting “Make into App Tab” from the context menu.
Web developers can animate content using CSS Transitions.
Responsiveness and scrolling improvements from the new retained layers layout system.
JavaScript speed improvements due to engine optimizations.
Changes to how XPCOM components are registered in order to help startup time and process separation.
Firefox 4 Beta 2 is available in 24 languages.
Tabs are now on top by default on Windows and OSX - Linux will be changing when the theme has been modified to support the change.
You can turn any tab into an “App Tab” by right-clicking on it and selecting “Make into App Tab” from the context menu.
Web developers can animate content using CSS Transitions.
Responsiveness and scrolling improvements from the new retained layers layout system.
JavaScript speed improvements due to engine optimizations.
Changes to how XPCOM components are registered in order to help startup time and process separation.

The biggest feature of the update is the addition of “App Tabs” which open every time you open a browser window and take up less room than a tab. You also can’t accidentally close them. This is great for things like webmail and streaming radio services that you might like to have off to the side while doing other browsing. When the feature is complete it will be persistent across browsing sessions.

Remember that all your add-ons still might not work right away. If you have something that you want the Firefox dev team to know about make sure you use the feedback button to the right of the navigation bar. A full set of release notes can be found on the Firefox 4 Beta 2 release notes page.