JavaScript WebSite Login Checker
This is a pretty original technique to check if you are loggued-in in known websites such Google, Gmail, MySpace, Blogger, MSN, ... The method is pretty original and works in many websites, so it's something you should know and be aware also. How does it work, very simple ! The JavaScript use a remote page from the service, simply in HTML, and load it as "Javascript", then check the error message returned for executing this HTML page. There should be at least one working page to test on it, I tryed the demo page and it's working fine with Flickr for example, error message might be changed for others. Adding new site by setting the error that should be detected for loggued as well as not loggued-in user and error line. Tested for Firefox 1.5 and 2 only.
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