Like the title says, if you want to upvote something on KBin, you should use the Boost link, not the upvote button (Why? Don’t know…)
The upvote button doesn’t seem to do much, but Boost accomplishes what Reddit’s upvote did. So if you’re looking to encourage a post, use the Boost link.
Importantly, boosts republish posts and comments. This is meaningful because groups work by basically boosting anything that mentions it, or which is in reply to something that mentions it. And posts silently mention the group.
Why is this important? Well, if you’re the first person on your instance to follow someone on another one, you don’t see anything published by that person earlier than that. But if that person regularly boosts older posts, you’ll get to see them.
So boosting posts and comments triggers the group to re-boost it, sending it out to servers that started following after the original publish time.
Basically, boosting is how we make sure new users on remote sites see older content.