I'm not expert on archiving. I have been using archive.is to archive web pages. I had assumed it also attempts to archive the embedded images of the page. However, that doesn't seem to be the case. I tried archiving this page:
https://forum.heatinghelp.com/discussion/143265/so-we-just-de-knuckleheaded-nickdus-steam-boiler
which gave me this:
but the image links have references to the original site. For instance:
https://archive.is/o/SO9bs/https://us.v-cdn.net/5021738/uploads/posts/14960/image.jpg
Seems kind of pointless. Though on the home page of archive.is it does say:
It saves a text and a graphical copy of the page for better accuracy
So maybe embedded images are out of scope. If so, are there archive sites which do archive the embedded images?
Archive.today (aka archive.is , archive.vn , archive.ph , etc.) does archive pictures.
However, it depends on sites to be coded according to proper standards, and the site you tried archiving was not.
Here's an archive of cnn.com and all the screenshots show up with no issues, as an example -
https://archive.is/96rwa
Seems related to me.
I can't help though.
Printing the page but changing the printer to "save as PDF" saves images, too, though, for offline, fwiw.