Private browsing

[1] The feature was subsequently adopted by other browsers, leading to the popularization of the term in 2008 by mainstream news outlets and computing websites during discussions about the beta versions of Internet Explorer 8.

[2][3][4] Adobe Flash Player 10.1 started respecting browser settings and private browsing modes in relation to storing local shared objects.

[13] It is a common misconception that private browsing modes can protect users from being tracked by other websites or their Internet service provider (ISP).

[21] This is one of the reasons why some browsers have partly addressed this shortcoming by offering additional privacy features that can be automatically enabled when using private browsing mode, such as Firefox's "Tracking Protection" feature to control use of web trackers (which has since been rolled into a larger "content blocking" function extended outside of private browsing mode), and Opera offering an in-house VPN service embedded within the browser.

[22][9] Brazilian researchers published the results of a project where they applied forensic techniques (namely the Foremost data carving tool and Strings program) to extract information about the users browsing activities on Internet Explorer and Firefox browsers with their private mode enabled.

To prevent circumvention of paywall policies and evasion of web tracking scripts used to monetize traffic, a number of websites — including The New York Times — have used such behavior to block access to users in private browsing mode, and requiring them to subscribe or log in.

[31] In December 2023, Google settled a $5 billion consumer privacy lawsuit that alleged its practises allowed it to track users in private browsing mode in various browsers.