You'll get this notification when you're about to launch Private Browsing.
Faster browsing and other tweaks
Beta 2 adds another feature aimed at protecting your privacy: It lets you erase your browsing history, cookies, download list and other browser traces from the last hour, two hours, four hours, today -- or all of your browsing history. In previous versions of Firefox, you could delete all of your history or none.
To use the feature, you select Tools --> Clear Recent History or Ctrl-Shift-Del. From the drop-down list, choose the time period for which you want to delete your traces and uncheck or check the specific traces you want deleted. Then click Clear Private Data.
This beta also turns on the use of TraceMonkey, a JavaScript engine that Mozilla says can speed up page rendering by up to 40 times compared to Firefox 3.0. In Beta 1 of Firefox 3.1, the engine was present but turned off. You had to edit Firefox using about:config in order to turn it on. In addition, this beta supports "Web workers" threads, a specification that lets Web-based applications run background processes. This should speed up Web-based applications, as long as developers take advantage of it.
As I worked with it, the beta certainly seemed zippier than previous versions, but further testing will be required to see how much faster it actually is.
Firefox has killed a feature that it had introduced in beta: the Ctrl-Tab function, which showed thumbnails when you cycled through open tabs. According to its release notes, Mozilla says it pulled the function "based on feedback from users." However, users who want to use it with the current version of Firefox need not fret, because that function was based on an existing Firefox add-in called Ctrl-Tab.
Also new to Beta 2 is support for the
Improved tab handling and Smart Location Bar
This version of the beta leaves in place a number of new features that were introduced with Beta 1 -- notably, changes to tab handling and the Smart Location Bar features. Starting with Beta 1, you can "tear" a tab from the tab bar by dragging it away and create a new, separate window out of it, something that Chrome allows, as well as other browsers such as Maxthon and Opera. Similarly, you can recombine tabs, and drag and drop tabs between instances of Firefox.
