Mozilla pulls day-old Firefox 16 from download site over security risk
 

One day after the release of Firefox 16, Mozilla said it has "temporarily removed" the latest version of its browser because of a security flaw that the company is trying to fix as quickly as possible. The unusual precaution suggests the flaw is a serious one, but there are no reports of it being exploited.

"The vulnerability could allow a malicious site to potentially determine which websites users have visited and have access to the URL or URL parameters," Mozilla Director of Security Assurance Michael Coates wrote. "At this time we have no indication that this vulnerability is currently being exploited in the wild."

http://arstechnica.com/security/2012...=Google+Reader

this is new in FF16, highlighting of keyword/letters in the URL bar?

edit: http://www.ghacks.net/2012/07/22/firefox-16-whats-new/