Produces persistent, respawning "super" cookies in a browser, abusing over a dozen techniques. Its goal is to identify users after they've removed standard cookies and other privacy data such as Flash cookies (LSOs), HTML5 storage, SilverLight storage, and others.
evercookie.js overwrites the window.name which in turn destroys the FB.Canvas.setSize method.
orginal name: "iframe_canvas_fb_https" new name: "iframe_canvas_fb_https&btag="
Don't mind the wrong btag.
From FB: NOTE: When using this method, ensure that window.name is not overridden as that can cause issues. (source: https://developers.facebook.com/docs/reference/javascript/FB.Canvas.setSize)