@niels This is useful question.
I've joked in the past that 'this Federation is great, when it works!'
Im not being negative at all, it quite complicated to always collate everything. Part of the problem is that although the ActivityPub is a 'standard' the other softwares have their own ways and interpretations.
As a test Im cc'ing another couple of accounts at different places, to see what arrives
@evehiclefan@mathstodon.xyz
@isurg@lemm.ee
@admin@isurg.org

@eeeee @isurg @admin
Notification arrived here instantly

Notification came here instantly too

And here instantly too. So this is working!

So 3/3 there, messages received and replies worked.

@eeeee Are time stamps sent with the post? Or created at arrival? If the latter, it's probably just that posts were sent to or processed by the Lemmy host in a different order than they were originally posted.

There's an inherent relativity of simlutaniaty issue with federation.

As you can see, mentions are pretty good at getting messages delivered both ways. The problem is getting messages that aren't replies to "real" forum posts. Try moving a big thread from somewhere on mastodon into a subforums and see what happens.

@Kichae Yes Lemmy isnt showing the posts in order it has them listed as x minutes ago! So thats something their end.
It may be the instance Im on hasnt updated and its been corrected since.

@niels @Kichae @eeeee what specifically you're asking for here is a way to retrieve the entire conversation, all branches of it, for the full context.

This is not something ActivityPub can do currently by design. However I am working with a number of separate implementors to establish something like this. You can see the progress of our efforts here:

The state of conversational contexts (February 2025)

A conversational context is what the ForumWG uses to describe what you might see as a reply tree or comment thread. One of the short-to-medium term goals of ...

NodeBB Community (community.nodebb.org)

This is already working in the wild. If you attempt to pull any post from NodeBB, you will get the entire topic, including remote replies.

Mastodon is separately working on something called "reply tree traversal", which is something that will also work but is an approach I feel is fraught with reliability issues.

@niels said in Moving fediverse thread into forum: Handling replies:
> Any future replies are not federated, unless they @ a forum user og any forum user follows the person replying (and even then maybe not, Fedi is Mysterious)

@julian This one's kind of interesting, as different fedi services seem to work differently, and group-based ones usually do some work to keep comments flowing. But nodeBB doesn't seem to always play nice with that at the moment.

I found a Lemmy post via url search and then moved it into a category. I then followed the group actor for the community. Posts and comments seem to flow fine in /world:

But the post that was moved receives no updates to speak of:

Interestingly, it does keep showing up in /unread as new comments are posted to the post on Lemmy, even though those comments never land in the topic on my forum, suggesting that nodeBB knows about them, but may not know where to put them:

@Kichae interesting! I'll have to test that flow. I've never tried moving a Lemmy topic in to a category and seeing whether future replies federate in properly.

@julian Great to see you working on it! My primary use case would be reading from Mastodon, any level of automatic retrieval would be an improvement.

I can see why you're excited about the new federation features, but whoa did you create a lot of work for yourself

@julian As an aside, I often use the @Fedilab@piaille.fr client for Mastodon. It has a fetch-all-replies button that usually works pretty well for Mastodon, and sometimes for other servers. If you copy that approach, it would pretty much fix my issue. But I have to admit I have only user-level understanding of ActivityPub, you might be working on something much better.

@niels @fedilab@piaille.fr likely uses reply tree traversal.

@niels Yeah, automatic retrieval isn't something one should currently expect from Mastodon. As julian mentions above, it doesn't currently proactively do anything to ensure completeness. It relies on the individual subscription relationships for that, and it doesn't work very well.

It currently makes the most sense to view ActivityPub as a technology that pulls in top-level posts into new social sites, for the users on that site to discuss amongst themselves (and the original poster), but this isn't what most users want it to be. People want, and seemingly expect, full discussion context. And so we see the discussions julian's involved in with other platform developers to land on some kind of standard way to extend ActivityPub for this stuff.

@Kichae @niels fwiw latest Mastodon just merged a PR that enables reply collection fetching. It's behind a feature flag and I'm guessing they're testing it out.

I'll likely write a little blurb about it and our approach this week

@julian Yeah, it's been a long time coming. The disparate views on single discussions was one of the uncanny things that killed the 2022 wave. That, quote posts, and people not groking the whole "the internet has more than 5 websites" thing, and the Masto devs have or are now taking action against all of those speed bumps.

Good on them for being responsive, I guess if not agile.

Just popping in here to say that this is probably highest on my wishlist for NodeBB - and also to understand whether this reply will end up in your context without me @'ing anyone

@malte@forum.fedi.dk yes, because you are using NodeBB. It will send the activity to as many people as it possibly can, who have any relation to the topic.