I want to prevent browser to close page in any case or in other case, Prevent browser to do anything when onbeforeunload is called.
Here is my code which i have tried.

 (function() {

    var proxied = window.onbeforeunload;

    window.onbeforeunload = function(e) {

        e.preventDefault();

        e.stopPropagation();

            //i want to stop everything

        console.log('stay here');

        // return 'message';

    };

})();

• I want to perform a action before leaving the page (disconnect the
  chat)