Or I can just hold (E: long press) your handle on the comment and do that from here. It's supposed to track from which comment you did that as well but I never tested it.
I'm also seeing numbers next to some people's name. It looks like its tracking net "karma" for the user? But its obviously not accurate (you have a [+4] as of writing).
That number should be how the total of upvotes and downvotes you have personally given that user. Useful for finding who to block when you see a troll comment and realize that nearly every comment you've seen from that user has been a waste of your time.
User tagging was what I was waiting for to try Voyager again (I prefer tagging users over blocking them), but per-user vote tracking was the killer feature I wanted an app to have.
I guess this is goodbye, Boost. Time to write a user tag import script!