What?s New in Firefox 3.6.9 Firefox 3.6.9 fixes the following issues found in previous versions of Firefox 3.6: * Introduced support for the X-FRAME-OPTIONS HTTP response header. Site owners can use this to mitigate clickjacking attacks by ensuring that their content is not embedded into other sites. The X-FRAME-OPTIONS HTTP response can be used to indicate whether or not a browser should be allowed to render a page in a <frame> or <iframe>. Sites can use this to avoid clickjacking attacks, by ensuring that their content is not embedded into other sites. The X-FRAME-OPTIONS HTTP response header can have two values, DENY and SAMEORIGIN, which will block any framing or framing by external sites, respectively.