Yes, but it's not guaranteed to be self-contained. I wouldn't want to open a random HTML file knowing that it could phone home, or that the content might break one day without me realizing. There's a practical and psychological aspect to sharing `steves_paper_2014.html` versus `steves_paper_2014.offlinesitebundle`. The latter feels safe and immutable.
>>jml7c5+(OP)
What you want is an HTML tag or response header that restricts network access, which the browser can then enforce. Offline or a list of allowed domains, this would be great for security in general. Not so great for advertisers though.
>>irq-1+Vf
Then you have to verify that the tag is there, right? But if it has another extension like .offlinebundle you can know thay browsers will not make any extra requests.