.arf file extension in Downloads, not in Overlay?

Hi! I’ve added the .arf extension (WebEx recording) to count as a Download by modifying our pages with
_paq.push([‘addDownloadExtensions’, “docx|pptx|xlsx|arf”]);

And I can now see the .arf accesses in the Downloads tab. But when I go to Overlay, the .arf file downloads are not showing up. What else do I need to do to have an extra file extension show up in Overlay?

Thanks!

PS We are on Piwik 2.16.1 and our site is behind a firewall, so I can’t give you the link.