Jmariamohlin,
Did you ever find a solution for this issue? I just had the same issue show up in my site and the URL popped up in my Broken Links Checker report. I can’t seem to find any information on what it is and it doesn’t show up in any virus/malware scans. The code is tagged at the end of my page and can only be seen in the code tab of the editor.
Thanks much! -JJ
This may come late to you but others might find it helpful. I found if you apply an improper page template to the calendar display page it will not show the calendar.