ah right! I forgot about that. For a single page:

(Firefox) load everything > ctrl+a > right click > view source (have to wait a bit for that to work) > ctrl+a again > copy > paste into text document > save as > example.html

It is a truly insane workflow, as if you are trying to do something weird.

Better to just right click > take screenshot > whole page or use the cli https://firefox-source-docs.mozilla.org/devtools-user/taking...