尝试:
navigator.__defineGetter__('userAgent', function(){ return 'foo' // customized user agent});navigator.userAgent; // 'foo'在FF2和FF3中进行了尝试。

尝试:
navigator.__defineGetter__('userAgent', function(){ return 'foo' // customized user agent});navigator.userAgent; // 'foo'在FF2和FF3中进行了尝试。