Keep comments collapsed upon re-entering post

[Outlet2048]

I often collapse top level comments to read other comments
After I'm done I go back to the previous screen

Sometimes it happen that I then conclude that aaaactually I'm not done with the previous post yet and that I want to continue reading something
So I click on the post again and everything is refreshing

It would be very handy to keep comments collapsed until the app restarts, the view is refreshed, or something else
I just don't think a full reload of the post is necessary whenever I open a post I've just viewed 5 seconds ago