Although committing the feature to the Github repository has finished, the feature will be available for you when your instance updates the Lemmy version to 0.20, 1.0, or higher.

Here’s the relevant issue: https://github.com/LemmyNet/jerboa/issues/1666

I believe that detection works for posts in the same community too. I posted two same links in a community and both was detected as cross-posted:

• https://lemm.ee/post/31756832
• https://lemm.ee/post/38772950

You can get the cross posts via API resposne. See cross_posts field in the response of https://<instance>/api/v3/post?id=<ID>.

Oddly, the endpoint on lemm.el and lemmy.ml return comments:

> curl 'https://lemm.ee/api/v3/comment/list?post_id=45734814' | jq '.comments.[] | .comment.content[:50]'
"Yeah, you're right. I didn't read enough of the do"
"Thank you for the tip ... but whatever I try with "
"~~In 0.19.5, they removed the deprecated `post_id`"

> curl 'https://lemmy.ml/api/v3/comment/list?post_id=21766749' | jq '.comments.[] | .comment.content[:50]'
"Yeah, you're right. I didn't read enough of the do"
"Thank you for the tip ... but whatever I try with "
"~~In 0.19.5, they removed the deprecated `post_id`"

I think it would be better to ask the admin of the instance before creating the issue.

I think GET /api/v3/resolve_object should work:

curl --url-query q=https://feddit.org/post/2401677 \
    https://lemmy.ml/api/v3/resolve_object \
    | jq .

(note that the value of q is url-encoded by --url-query)

You can get 50 items at most with limit=50. Try

https://lemmy.ml/feeds/c/lemmy_support.xml?sort=New&limit=50

Not a direct solution but GET /api/v3/site may help.

Maybe some rules in nginx.conf has been delegated to nginx-internal.conf.

I suspect your instance was used to backup the original communities.

You shouldn’t post the auth value here - it works like a username and password.

I grepped the source and found

• https://github.com/LemmyNet/lemmy/blob/0.18.2/crates/apub/src/objects/post.rs#L53
• https://github.com/LemmyNet/lemmy/blob/0.18.2/crates/db_schema/src/schema.rs#L645

Can you run the code against another instance, and curl https://lemmy.ml/api/v3/post/list?

What happens when you call POST /api/v3/usre/login after the 400? Do you get another JWT token or the same one?