GP is using SingleFile browser extension. Which allows him to download the entire page as a single .html file. But SingleFile also allows sending that page to Karakeep directly instead of downloading it to his local file system. (if he's hosting karakeep on a NAS on his network). He can then use the mobile app or Karakeep web UI to search and view that archived page. Karakeep does the indexing. (Including auto-tagging via LLM)

I see now, thank you.