Markitup Icons Missing

I updated Perch to 2.8.23 including the Markitup folder, but the icons that usually appear in the body tag (H1, H2, Bold, Italics, etc.) are not showing up. I thought it was a cache problem, but I've cleared my cache and even tried a completely different browser.

Any ideas to why these icons would not be showing up?

This is an example of the content tag I'm using:

<perch:content id="mainbody" type="textarea" label="Main Body" textile="true" editor="markitup" required="true" html="true" />