Recording/saving videos from add-ons (NOT live)

Hello all,

After much hesitation I decided to post this question, as I was unable to find any pointers thus far. I am running osmc on a RPi 1. I watch only offline videos from the video add-ons, no live TV. Given that they are often removed after a week or so, I would like to be able to record/save them. In my understanding this is quite different from (and possibly simpler than) recording live TV. How should I go about that?