If you enable a plugin, you still need to include its original CSS in your app if there is one.
Internet Explorer Note:
Current CSS selector count exceeds limitations of IE9 & below.
Therefore the extra part should be saved and included as a separate CSS file.
Please save it and use the following IE conditional comment to include it:
<link rel="stylesheet" href="path/to/ace.css" />
<!--[if lte IE 9]>
<link rel="stylesheet" href="path/to/ace-part2.css" />
Read about this IE limitation