I also use my own, lets say search engine.

I download only title, description, thumbnail, common og fields.

My index is very lean, I think. I have 2m of pages crawled.

https://github.com/rumca-js/Internet-Places-Database

It has tags, and votes support.

Recently I also launched my first fdroid app

https://github.com/rumca-js/OfflineWebSearch

https://f-droid.org/en/packages/io.github.rumcajs.offlineweb...