title: Setting transparent background on a button isn't working in IE9
body: <p>I have an ExtJS app where I'm using some toolbars with a background behind them so I'm making the toolbars and the buttons transparent.  Some of my users are still stuck on IE9 (I know) and the buttons aren't displaying correctly.</p>
  
  <p>See fiddle here for an example: <a href="http://jsfiddle.net/qmy4nu30/" rel="nofollow noreferrer">fiddle</a></p>
  
  <p>In Chrome, or IE 10+, the toolbar button is transparent.  It looks like this: <a href="https://i.stack.imgur.com/m3vMI.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/m3vMI.png" alt="enter image description here"></a></p>
  
  <p>In, IE9 however, it looks like this: <a href="https://i.stack.imgur.com/1OXUS.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/1OXUS.png" alt="enter image description here"></a></p>
  
  <p>Fiddle code: </p>
  
  <pre><code> Ext.onReady(function () {
        var win = Ext.create('Ext.window.Window', {
            layout: 'fit',
            height: 300,
            width: 300,
            autoShow: true,
            tbar: {
                style:'background-color:orange;',
                items: [{
                    text: 'hi',
                    style: 'background:transparent;'
                }]
            },
            html:'some html'
        });
    });
  </code></pre>