The only element is the name of the community
Consider community names hashtags.
Comment on Question: why mastodon hastag timeline shows posts from lemmy community of same name?
lgsp@feddit.it 1 day agoMmh, that’s not an explanation: when I look at an hastag timeline in mastodon, I expect to see all the posts that federate with my server and contain the relevant hastag.
In this case I for sure see also posts that are federated, but, AFAIK, do not contain the hashtag. The only element is the name of the community
MelodiousFunk@slrpnk.net 1 day ago
cecilkorik@lemmy.ca 1 day ago
According to the protocol they share (ActivityPub) communities and hashtags are essentially the same thing, they’re a grouping containing many posts. Typing out a hashtag is how you tell Mastodon to add your post to that “hashtag group” (and you can add your post to multiple hashtags). In Lemmy, the community you post in IS the group (and you can cross-post it to multiple communities). The result is the same. They’re the same thing, just different ways of connecting your posts into them, and displayed in very different ways depending on which part of the Fediverse you’re using.
30p87@feddit.org 1 day ago
The confusing part is that it didn’t work most of the time. This seems to be a very recent change. Before, and still now, you could only post to lemmy communities by tagging them with @. Now they federate back, but as hashtags.
schnurrito@discuss.tchncs.de 1 day ago
No, this is false as far as I can tell. I am willing to be corrected by someone more knowledgeable but my understanding is:
Communities are implemented not as hashtags, but as special users who “boost” everything addressed to them. That is why Lemmy sometimes gets posts made on Mastodon that mention a Lemmy community. It doesn’t always look great: discuss.tchncs.de/post/45785836
So communities and hashtags aren’t the same thing. In particular, communities have moderators who can remove things or ban people. Hashtags don’t.
It is a feature of Lemmy that all new posts (not, AFAIK, comments) also get the community name added as a hashtag. This is what OP was seeing and serves to somewhat increase the reach of Lemmy posts. But you can’t follow microblog hashtags on Lemmy.