Ask HN: How to archive online content?

Online content has a habit of disappearing. Sometimes I have a link to an article from a few years back, I go to it and there is nothing there. 404 or someone migrated the platform to a new engine, but did not bother to preserve the old stuff. Sometimes people get emotional about the content they created and take it all down. A lot of times it is all actually pretty high-quality. Sometimes YouTube takes something down for various reasons.

I would like to be able to archive things I find especially worthwhile, but the web doesn't seem to be built to make it easy. Downloading the website with a browser's in-built function "Save page" breaks it (relative links, you don't really download the whole page etc.) - something that doesn't happen with Office documents, PDFs, just about anything that is meant to be moved around. Websites seem to be heavily glued just one place.

To fix these problems I used to convert a bunch of articles to LaTeX, generate a PDF and be done with it. However, frequent LaTeX editing is tiresome. Pocket seems to be an option, but sometimes it fails to archive an article and just redirects you to the original version; what's more it is a service just like YouTube, so I really have no guarantees of preserving the things I save there.

Do you have any good semi-automatic methods for archiving online content?