No, I understand, it's just that I am following the group actors. I'm following the Lemmy communities from here, but new posts from them aren't arriving. I'm following the nodeBB topics from Lemmy, but nodeBB user comments aren't showing up there.

Lemmy only supports following group actors. So, Lemmy communities, gup.pe groups, PeerTube channels, NodeBB topics, etc. If NodeBB's federation is reliant specifically on following users, that represents a fundamental difference in the federation models between the platforms.

@Kichae no the group actors are fine too. We implement the same sharing system that Lemmy implements.

Hmm, ok. Unexpected and unintended interactions (or lack there of) it is, then. Fun!

Edit: This comment, FWIW, showed up in Lemmy right away. So, whatever the issue with on-site comments not federating out seems to have been resolved. If no active intervention was taken, it may have been an issue with Lemmy 0.19.3 (lemmy.ca just updated the other day to 0.19.7, IIRC), or it may have just been federation queue issues.

Edit Edit: I love that federated comment chains can be forked without breaking federation. That's awesome.

@Kichae the forking is local only. There's no standard way to communicate a fork action across to other instances.

We'll try to be pioneers and come up with a way though!

I was worried that forking just wouldn't be supported on federated topics, or that if a posted was forked, it would break federation. So, this is incredible. This is what I've been waiting 2 and a half years for.

@Kichae yeah let's say a topic is forked in NodeBB. The baseline expectation is that federation doesn't break, but the ideal is that the fork is also federated so Lemmy (for example) would also fork the topic on their end, so it looks the same on either end.

Something we'd want to work on with ForumWG (specifically @trwnh@mastodon.social)

It's happening!

Almost everything here in the attached image is coming from comicstrips@lemmy.world, a Lemmy community (Christine Lemmer-Webber excepted). So, that's exciting! There's some inconsistencies with regards to whether the attached images are coming through, and whether community is being tagged or not, but that's just rough edges. Image-based communities aren't as much of a forum thing anyway.

@Kichae hmm they ought to work the same though, so inconsistencies should be addressed. Thanks for letting me know. I'll take a look today, time permitting.

The difference appears to be whether the OP is on lemmy.world (LW; the site that hosts the community) or not. Posts made by LW users do not include the tag or media, while posts made by off-site users do contain the tag and media.

@Kichae With regard to some responses showing up and others not, it seems Lemmy does not process activities for communities if it has no followers.

So let's say you search for a remote community on Lemmy and make a post to it, and it crosses over to NodeBB. If that community has no local followers then even though you posted to it, any replies will not be accepted by Lemmy.

Seems like a bug or restriction on their part.

@Kichae said in Lemmy and NodeBB:

No, I understand, it's just that I am following the group actors. I'm following the Lemmy communities from here, but new posts from them aren't arriving. I'm following the nodeBB topics from Lemmy, but nodeBB user comments aren't showing up there.

At least in my limited (and definitely not exhaustive) testing, bi-directional posting does seem to work.