@infinite love ⴳ The concept of a thread is probably older than most people in this conversation. It is at least 40 to 50 years old now. I don't think we should change the definition that every email client, forum, and discussion group has used for decades.

Yes, I agree that on the backend, a lot of the stuff is the same but with a different UI. I get it. In fact, I am someone who frequently brings that up.

But there are some very practical considerations on why a thread should be treated differently than a context or collection. And that is mostly because the UI to display a conversation is different than the UI for displaying a collection.

So there needs to be some way to indicate where to retrieve the entire thread.

@infinite love ⴳ Let's look at the practical aspects.

Most platforms that have threaded conversations have two different views: one for threads, and one for collections or lists.

For a blog it is usually presented as the blog post with comment (a thread) vs. a list of posts in a category or as search results (a collection).

For a forum, it is similar, with a top level post and its replies (a thread) vs. a list of posts in a category or as search results (a collection).

For a discussion group, it is the same as the forum, but the UI is different.

For email, you have a threaded conversation (an email and its replies) vs. a list of posts in a category or as search results (a collection).

Notice that they are all similar. Notice that they all have something in common. There are two views, and threads always only have one parent or top level post.

From a very practical developer perspective, I need to choose which view is used to present the posts. Threaded conversations get presented one way, and collections get presented another way.

It would be nice if ActivityPub actually told me whether this is a thread or a collection so I can choose the appropriate user interface.

@scott Those are all just lists, though. If you needed more hinting as to what type of collection you're viewing, then you can declare types like Thread or SearchResults or MediaAlbum or whatever. But hardcoding a check for a specific type is fragile.

The only practical consideration is in knowing whether you can submit an object for inclusion (this is the missing bit, we need a property like "can participate"), and where to send it for consideration (attributedTo).

@infinite love ⴳ Yes, on the backend they are both lists.

But the UI is VERY different for conversations versus lists.

Since the UI is different for conversations and list, I need to know whether it is a thread or a list of random posts so that I can display it correctly.

@trwnh @erincandescent @julian @mikedev @silverpill You haven't been thinking about this problem nearly as long as I have. Who do you think created `ostatus:conversation`?

Anyway, I think we agree on more than we disagree on. We both think `context` should be for general groupings.

We both think the thread identifier should be a dereferenceable collection, and that the original post creator should emit `Add` activities to show that it's been updated.

@trwnh @erincandescent @julian @mikedev @silverpill I think the reply tree is essential and should have its own property so it's easy to find and use, rather than having to guess if what's in the `context` collection is a reply tree. You don't; that's too bad.

@evan @erincandescent @julian @mikedev @silverpill It’s not about how long one thinks about it, moreso that this idea of “generic data with specific presentations” didn’t come out of nowhere overnight. We shouldn’t overfit our data model to any specific presentation. It would be a great shame to continue privileging inReplyTo above other metadata; it represents a form of context collapse, because responding to something shouldn’t be a stand-in for an actual conversation.

@evan @erincandescent @julian @mikedev @silverpill Basically, I’ve seen and directly experienced so many cases where a conversation is not and should not be the same as a reply tree, and where conflating the two has created problems on conceptual, technical, and social layers. They exist separately, and have different semantic properties. Consider that someone making a post inReplyTo something else may not actually be participating in the same conversation, or any at all!

@infinite love ⴳ @Evan Prodromou This is exactly why platforms that have threads should declare that it is a thread. The reply tree does not always indicate whether it is a thread.

If the reply belongs in a conversation container, the container should be mentioned via ActivityPub. That way the receiving platform can display it properly.

(Thread = Conversation = Conversation Container & its Posts)

@trwnh@mastodon.social @evan@cosocial.ca I have the feeling we're getting too into the woods about defining what exactly a thread or context ought to contain and specifying that those definitions need to persist across all implementations.

I don't think they have to.

NodeBB considers a conversational context as a "topic"/"thread". ForumWG decided to refer to these as "contexts" for ease of discussion, but other software need not follow that paradigm.

If one implementor decided to utilise context to contain only one specific line of objects (a "sacred timeline thread", if you will), I'd argue that's a perfectly valid use of context, and also fits into the definition of both of your FEPs. When they pull a NodeBB context they'll get what NodeBB thinks is a context (the entire reply tree), and that's okay too.

Basically, my argument is that yeah, as Evan said:

Anyway, I think we agree on more than we disagree on.

When we step back and think about what we want to achieve:

1. Ability to reliably backfill a conversational context
2. Declare a context owner that acts as a canonical source for context additions/removals (reply limiting and such)

Then what we're left with are three FEPs (7888, 171b, 763a) that all fit the bill but only differ in minor technical aspects.

If we're going to talk about favouring FEPs over minor technical aspects, need I remind you of the following from @jenniferplusplus@hachyderm.io:

I continue to feel that this general idea is in keeping with the as-written intent of the context property. Adding a new property is likely to make adoption slower and more complicated. Adding a new object type is also likely to make adoption slower and more complicated, but less so than the property.

The more complicated you make something, the fewer implementors you're going to get. I haven't thought about these concepts nearly as long as you two have, but especially when you're talking about volunteer developers who have to work with other volunteer developers, any stumbling blocks could become insurmountable.

Simply put: there's a reason when someone wants to use OAuth2 SSO on NodeBB it's a free plugin, and when they want to hook into their corporate SAML SSO I charge a rather hefty sum.

@trwnh@mastodon.social @evan@cosocial.ca

@julian How I view it is:

1. What information is being transmitted now?
2. What information do we want to have?

We will always have to deal with implementations that vary, and we sometimes will have to assume things because they did not send all of the information we need.

But, we can still say "we would prefer the information be sent in this format." especially if that format includes additional information that tells us how to render it properly.

So there is a difference between the minimum amount of information we need and what information we want to have.

Or put another way, we can provide a way in the spec to declare that something is a thread, but still be able to process the data without it (by making assumptions since we are missing some of the data).

@julian I think including the thread in the `context` property is fine; I think saying that the only thing that should go in `context` is the thread is not OK.

If you're concerned about simplicity, having a clear property to use only for the thread is the way to go.

@evan@cosocial.ca in that case if @trwnh@mastodon.social were to relax their restrictions on what context can contain to include both conversational contexts and reply trees, would that be sufficient?

@julian @evan That restriction doesn’t exist; technically the collection contains whatever the owner adds to it. Putting `context` on your object is no guarantee your object will end up in there. Neither will `inReplyTo`.

`context` should be used for grouping, but specifically for a *purposeful* grouping. At its base, it’s like a fancy hashtag, but instead of being a simple reference, it imparts meaning and understanding when you consider the object “in context of” it.

@julian @evan The problem is in social expectations. If I send you an object from a generic AP server that declares “inReplyTo” but a different “context”, it would violate my expectation for that object to end up in a different topic than the one i asked to be included in. But sending it from Mastodon, the calculus changes: Mastodon currently doesn’t support the concept of a reified thread as separate from the reply tree, so NodeBB including that post would be a fallback.

@julian @evan So the ideal would be signaling on the actor (or jumping ahead in theoretical developments, on the client attached to the actor) that a certain protocol is being followed. That way you don’t have to make guesses and uncertain assumptions.

And then I would ideally be able to send you an object for consideration to include in some collection. It seems reasonable to say that me declaring one of your contexts should be the primary consideration for inclusion.

@julian @evan But as Evan points out:

> saying that the only thing that should go in `context` is the thread is not OK.

It is possible that any given context may be a Person, or an Event, or a Place, or whatever. (This probably makes more sense in a GTD tasks app than in a forum software.)

It’s also possible it may be an opaque URI.

Nevertheless, if you can’t extract any useful information from it, you drop it from consideration. No owner means no one to address.

@julian @evan What 7888 tries to do is describe a potential generic framework for how to process objects declaring a `context`, all the way up from the base case (missing) to the simplest case (an opaque URI) and building upwards from there. This is similar to how you might process objects declaring a `tag` array to detect rich entities within the textual content of the post (mentions, hashtags, links, potentially quotes, emojis, whatever the future brings)

@julian @evan The “missing bit” is a signal for participation; in other words, a property and/or type that means “if i send an object matching a certain shape to the owner, they might add it to this collection.” Right now this is implicit; it would be better if it were explicit.