!!! Overview
[{$pagename}] is defined in [RFC 7519] as a [JSON] [string] value, with the additional requirement that while arbitrary string values MAY be used, any value containing a ":" character [MUST] be a [URI] [RFC 3986].  

[{$pagename}] values are compared as [case-sensitive] [strings] with no transformations or canonicalizations applied.

!! More Information
There might be more information for this subject on one of the following:
[{ReferringPagesPlugin before='*' after='\n' }]