We use to be able to unfollow a post

Can we still unfollow a post? if yes how?

EDIT: @JeffreyWay I remember we used to be able to do this. Is this a part of the app that may still be broken?

EDIT EDIT It looks like just the checkmark and the word 'FOLLOW', or 'FOLLOWING' on the button are out of sync with the actual state, because when I filter by Following and open one of the posts that I am following. The button say's follow and when I click it it gives a toast that say's I am now following but in fact it is removed from Following.