SharePoint 2013 - Anonymous Site - Chrome SharePoint Plugin

I asked this on Stack Overflow as well.

When anonymously browsing a SharePoint 2013 site configured for anonymous access:

Chrome for Mac displays: Could not load SharePoint Browser Plug-in.

and

Chrome for Windows displays: Microsoft Office needs your permission to run.

What is embedded in the page that makes Chrome want to run a plugin, and how can I remove it? I can't seem to find anything about this, apologies if it has been answered.

Thanks, Kaveh