At first I could not believe that this extension really combines ALL assets in a single HTML file, that a 1:1 image of a page can be archived with correct display (including all links).

After seeing the saved file, I saw images converted to base64, but still couldn't believe that at least external links to JS and CSS files are not used here: so turned off the internet connection and cleared the browser cache. Result: the page was still displayed correctly!
It really does combine HTML and all assets into one single HTML file.

This is really impressive!

As another user remarked: we've been wishing for this since the 1990s! Wow. Thank you!