All posts show as "crossposted to:" in the small space between the Fediverse, star etc icons and the post
What did not happen in your case is having "crossposted from" in the body of the text. Probably a client issue indeed (or maybe a decision, as IIRC Thunder aggregates comments from all crossposts together? Or maybe it's another client?)
The body of posts is submitted by the user. I've personally never noticed "crossposted from" in the body of a post. Whereas the crossposted metadata is stored separately on the server.
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?)
Huh, then you worded your comment kind of strangely.
In any case, I think the rest of my comment applies then. It's a feature of the web UI and not one that is particularly useful in my opinion since the post already contains metadata about cross posts, and Thunder displays the age of all of the crossposts making it pretty easy to identify the original. (Unless the crosspost was done at the same time as the original post, which usually indicated the original author was posting it in several places at once, in which case which one is really "the original"?)
If the web UI doesn't show this data, then that's the fault of the web UI.
Thunder displays the age of all of the crossposts making it pretty easy to identify the original.
That's probably the main difference here.
The web UI does not show the age of the crossposts, so I guess the devs used the "let's inject the source in the body of the crossposts" as a workaround for that
On the other hand, having the web UI copy pasting the body of the source is still useful.
That's why the commenter pointed it out on this comment: https://lemmy.ca/post/29880029/11900447 , as your crosspost was missing the additional information you added in the body of the original post
Edit: thought you were the OP, but that's still valid
their crosspost was missing the additional information they added in the body of the original post
What do you mean "missing"? Are cross posts supposed to copy over the original post body? Post bodies often contain notes specifically for the community they are posted in and you wouldn't want the original body. Just the link and your own post body. Even if they are copied, you can certainly remove that text and write your own. Hell, you could just delete the "crossposted from" note, too!
This is not a bug. It's a tiny feature the web UI does that Thunder chose not to implement.
(I fixed your nouns in the quote. You should have just done that in your edit.)
Edit: indeed, the web UI quotes the entire original post body and adds the cross post note. You are free to delete all of it.
I realize, in this case, crossposting this post without also adding a body explaining the post is a little odd. But it's always the poster's choice to add or modify the post body after clicking crosspost. Could Thunder add a feature to copy the original body as a quote? Sure. But it's not a big.