This feature is a a save as... feature. As of now Chrome allows me to save a website as "Website, HTML only" or "Website, Complete". The problem with this is when you save a website as complete it makes a .html and a folder with a bunch of icons and such (if those ever get deleted it so effects the .html link provided with it by not displaying them). However, this save as... feature is ever so better in Opera. If I want to save a website page I click save as... on Opera and it gives me a "Website, Single File" feature which saves a .mht file on my computer without a folder with a bunch of pictures with it (it basically makes a scrollable screenshot of the page & adds links which when clicked will bring you to the page just like you were browsing the normal site).
I would love to see this feature added to Iron

Sincerely,
StatenJM