Yeah this is the thing that comes to mind for me as well – something like the “back” button we currently have on the timeline that appears of you scroll in the other direction, but to go to the beginning of your first unread post instead.
I could imagine it being a user preference as to whether it shows up or not.
I have wanted this in the past, but personally haven’t felt a need for it recently, so the stories do help to understand where the request is coming from, thank you.