I made a diagram to help you understand how the different timelines/columns work:

https://techn.ical.ist/assets/help.svg https://techn.ical.ist/media/zhoMEHOzhT2r6zlz034

@vhf this isn't quite complete in a way I haven't figured out yet. For example, I can see your toot on my (single user) server's federated timeline even though I don't follow you.
@pete Do you follow someone who fav'd or boosted my toot?
@vhf Is there a way for me to determine that? I can just see the counts on the toot permalink.
@pete @vhf I boosted it, if you follow this account
@djsundog @vhf I don't. I follow a bunch of people though, so if like/boost from a follower is a trigger as well that would explain it.