I just crossposted something using Thunder and another user let me know that my crosspost did not show that the other post was the original.
See here: https://lemmy.ca/comment/11901004
Not sure how that can happen but seems like a bug in Thunder then?
If the post body is empty, nothing happens.
Otherwise:
Even here, clicking on the crosspost icon from the web UI creates this:
Edit: Maybe I misunderstood. Are you implying that Thunder does this, too, but only if there’s already content in the post body?
Ah, sounds like it’s a web UI front-end feature then. It just sticks that text in there for you. That’s odd when there’s back-end data that contains the cross post information and accessible from the API.
(At least that’s my assumption. Thunder shows crosspost data in a handy table. I feel certain it’s not generating this data on its own from some kind of search. The database must already contain this data and have an API for it, so why does the web UI stuff it into the post body at the same time?)
There is no special backend data, and lemmy makes no distinction between which post is “original” aside from the difference in the timestamp.
Lemmy simply hooks up all posts into cross-posts that link the same URL.