The main feature of this beta was the function “ Do Not Track ” ( Do Not Track ), allowing you to better maintain the confidentiality of users. You can check the corresponding checkbox in the settings, and the sites will receive a signal that you would like to avoid tracking your behavior. ')
A full list of bug fixes is available on this page: www.mozilla.com/en-US/firefox/4.0b11/releasenotes/buglist.html