title: Open new window in new tab
body: <p>I am trying to open a new window when user click on button as follows:</p>
  
  <pre><code>protected assignActity(type: string): void {
      var window = window.open('/#/link');
      this.Service.assignActivity(type).subscribe(res =&gt; {
        window.location = '/#/link/' + res;
        console.log(res);
      })
    }
  </code></pre>
  
  <p>but it's throwing an error:</p>
  
  <pre><code>core.umd.js:3468 TypeError: Cannot read property 'open' of undefined
  </code></pre>
  
  <p>How to correct it to get it working?</p>