Mozilla plans to add a private browsing mode when it releases Firefox 3.1, expected in beta by mid-October.
In private mode, all browser activity is discarded from the user's personal computer as soon as the user returns to normal mode.
Mike Beltzner, phenomenologist at Mozilla, told SCMagazineUS.com on Friday that though the user interface details aren't completely worked out yet, Mozilla is looking closely at what is involved in securing private browsing data.
“Primarily there will be a way to enter and exit a ‘mode' where no browsing data is being recorded, but we're also investigating things like being able to easily select a portion of your browsing history to be excised,” Beltzner said. “For example, it should be possible to say, 'Consider the past two hours of web browsing to be private.'”
Another possible security benefit, Beltzner said, is that with increased control over what parts of the browsing history are stored on the computer, the private browsing mode enables Firefox users in shared and public computing environments to work without revealing sensitive information about themselves.
“We're also looking at restricting access to a user's cookies, so that when they're in private browsing mode, we don't leak their personal information to websites that they are browsing,” Beltzner added.
While the private browsing modes are good at protecting information on shared computers, it doesn't affect the information stored on servers.
“Your mother or your spouse may not be able to follow what you're doing,” Gartner analyst Avivah Litan told SCMagazineUS.com, “but there are still bigger privacy issues out there.”
On the other hand, she added, it's good to see the browser companies competing over privacy issues.
“Privacy has become an important consumer issue,” she said, “and I'm glad the browsers are taking these steps. But they need to also make sure they can assure their customers that their data isn't being tracked on servers.”
The beta versions of Internet Explorer 8 and Google Chrome also include private browsing modes.