[manifest] Is RFC5988 supported by implementers? (#424)

The last sentence of the spec's Abstract section mentions a document can be associated with a manifest "either directly in an HTML document or over the wire using RFC5988"  (https://tools.ietf.org/html/rfc5988) 

If I understand correctly, the directly in a HTML document would by via:
<link rel="manifest" href="..." >

And via RFC5988 would be a HTTP header:
Link: http://...; rel="manifest"

If referencing a manifest via RFC5988 is somewhat common and/or supported by implementers, I recommend we elaborate on this as a new section 5.2

If referencing a manifest via RFC5988 is very rare and/or not supported by implementers, I recommend considering removing the reference to this method in the Abstract section.  

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Reply to this email directly or view it on GitHub:
https://github.com/w3c/manifest/issues/424