Allowing display toggle state to persist across multiple sessions

We are just about to test the Collapsed Topics course format as it seems like a good compromise between the default Topics (show everything in a long scroll) and showing just one week.

The fact that the toggle state for each user resets for each session seems like a limitation - it might be better if users/teachers could choose whether the toggle state persists across sessions or not. I'm not a programmer, but this idea seems feasible to me with either cookies or database entries.