2/

Because most people wouldn't be able to add custom attributes or custom values to most Fediverse software (including Mastodon) —

Most supporting software would probably want to support a "PropertyValue" link in "attachment" field as a fall-back

For example:

"attachment": [
{
"type": "PropertyValue",
"name": "Video Calls (callpub)",
"value": "https://videocalls.example/users/joeblow"
}

But —

...

3/

But, what about the non- fall-back situation where software could properly support this (when an Actor specifies a list of Service actors associated with it)‽

I think some might say, put the associated Service actors in "attachment". And, semantically I think that would work with ActivityPub, but — I have a very strong dislike with putting everything in "attachment" (and "tag"). It makes parsing difficult.

So —

0

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