BO, BV, CM etc are busy keeping things running smoothly, but all the same, I recommend making high-fidelity HTML archives of full threads here.

https://addons.mozilla.org/en-US/firefox/addon/save-page-we/

https://chrome.google.com/webstore/detail/save-page-we/dhhpefjklgkmgeafimnjhojgjamoafof

A typical thread takes up 10 - 20 MB of space saved this way. If there are images you want to save in full, rather than just thumbnails, you can expand them first. This will take up more space of course.