Saving the edited content on Firefox didn’t work until I read in TFA on Hacker News that you have to save as “Webpage - Complete”.
Rob @Beschizza, your version works a little better in this regard since it doesn’t create that additional “new-note_files” folder to store the CSS and JS that the original one does. Haven’t tried in Chrome yet.
Side benefit: this is a quick way to create a base64 version of an image.