I gave up a long time ago and started using the "Save as..." on browsers again. At the end of the day, I am interested in the actual content and not the look/feel of the page.
I find it easier to just mass delete assets I don't want from the "pageTitle_files/" directory (js, images, google-analytics.js, etc).
Save as doesn't work on sites that lazy load.
Have you https://addons.mozilla.org/firefox/addon/single-file/?
If you really just want the text content you could just save markdown using something like https://addons.mozilla.org/firefox/addon/llmfeeder/.