private addFbScript(): void {
      (window as any).fbAsyncInit = () => {
        FB.init({
          appId: environment.fbKey,
          cookie: true,
          xfbml: true,
          version: 'v4.0'
        });
        FB.AppEvents.logPageView();
      };

      (((d, s, id) => {
         let js, fjs = d.getElementsByTagName(s)[0];
         if (d.getElementById(id)) {return; }
         js = d.createElement(s); js.id = id;
         js.src = 'https://connect.facebook.net/en_US/sdk.js';
         fjs.parentNode.insertBefore(js, fjs);
       })(document, 'script', 'facebook-jssdk'));
  }

private addFbScript(): void {
      (window as any).fbAsyncInit = () => {
        FB.init({
          appId: environment.fbKey,
          cookie: true,
          xfbml: true,
          version: 'v4.0'
        });
        FB.AppEvents.logPageView();
      };

      (((d, s, id) => {
         let js, fjs = d.getElementsByTagName(s)[0];
         if (d.getElementById(id)) {return; }
         js = d.createElement(s); js.id = id;
         js.src = 'https://connect.facebook.net/en_US/sdk.js';
         fjs.parentNode.insertBefore(js, fjs);
       })(document, 'script', 'facebook-jssdk'));
  }