Add the Collapse option at the bottom of some Activities

I’m referring to the Collapse option which is currently available only from the activity header:

Some activities (for example, a Sequence) may contain many sub-activities within them and therefore extend to a long scroll, such that when the user works on the bottom of the parent activity, its header is not visible and is reachable only via a long scroll up:

Therefore it would be helpful to have the Collapse option also from the bottom (footer) of such activities, something like this (illustration image):

Thanks for your suggestion.