5 years ago, I wrote about rolling my own read-it-later solution.
https://njoseph.me/blog/posts/read-it-later-solution/
There's a less hacky/much better solution now.
https://readeck.org/
It's self-hostable, AGPLv3 licensed and hosted on Codeberg.
Found it featured on Codeberg blog. https://blog.codeberg.org/letter-from-codeberg-onwards-and-upwards.html