I have a page that redirects to other page I try to test my url on: https://developers.facebook.com/tools/debug i get this error: Errors That Must Be Fixed: Circular Redirect:? Circular redirect path detected (see Redirect Path section for details). Warnings That Should Be Fixed: ?The og:url property should be explicitly provided, even if a value can be inferred from other tags.? how can i fix this problem? how to detect facebook and if it is facebook dont redirect?