Thanks for the reply! That link was helpful in figuring out why this is happening but, unfortunatley, it won't solve the issue since we can't depend on our CMS users to be able to update their Chrome client to disable the XSS auditor.
My Chrome versions is Version 67.0.3396.62 (Official Build) (64-bit)
I pasted the error I recieved in the opening question unless you meant something else.
I've actually discovered this issue is occuring in other browsers as well - not just Chrome. The issue seems to be that the WYSIWYG editor can't contain any JS scripts. If anyone knows of a way to be able to get a JS script to work in the WYSIWYG editor then that should solve the issue.
Thanks in advance, Kenticans!