The big problem with the button

[Moritto]

I started watching the video tutorials to create an application. There’s a man got to stick button and I have not! Tell me what could be the problem here? I can not insert a tag

That application code

<link rel="manifest" href="manifest.json">

<!-- un-comment this code to enable service worker
<script>
  if ('serviceWorker' in navigator) {
    navigator.serviceWorker.register('service-worker.js')
      .then(() => console.log('service worker installed'))
      .catch(err => console.log('Error', err));
  }
</script>-->

<link href="lib/ionic/css/ionic.css" rel="stylesheet">
<link href="css/style.css" rel="stylesheet">

<!-- IF using Sass (run gulp sass first), then uncomment below and remove the CSS includes above
<link href="css/ionic.app.css" rel="stylesheet">
-->

<!-- ionic/angularjs js -->
<script src="lib/ionic/js/ionic.bundle.js"></script>

<!-- cordova script (this will be a 404 during development) -->
<script src="cordova.js"></script>

<!-- your app's js -->
<script src="js/app.js"></script>

<ion-pane>
  <ion-header-bar class="bar-positive">
    <h1 class="title">Hacker proga</h1>

<button class="button icon ion-plus>

  <ion-content>

{{task.title}}

[Moritto]

I help somebody?I found a mistake and correct the developers!

[max]

What’s the issue? I don’t follow.

[PterPmnta]

Sorry, the problem is some about the button in the navbar?

[Moritto]

The buttons are superimposed on each other.
Normally everything should look like this, only need to add on the top right icon.

Button does not want to be added to the header!