Technically, the changeset is from RapiD Editor. This is clear from the “created_by” and the “host” and I’m not the developer of the OSM-API, but I think it’s not that easy to manipulate. The #maproulette, on the other hand, was interpreted as a hashtag and thus comes from the changeset comment. But let me try this live.
I started the RapiD editor (without having MapRoulette in the game). I simply added a building as an example with RapiD. I added “added a building” as a comment and submitted it: Changeset: 162504232 | OpenStreetMap
Now let’s do the same again, but I’ll just type #maproulette as the comment for this changeset to see what happens: Changeset: 162504326 | OpenStreetMap
In the second screenshot, but also in the second linked changeset, you can see that #maproulette is now in the changeset. I didn’t do anything with MapRoulette here, I just added the changeset comment by hand.
