If this isn’t Discourse’s fault, I’ll take this to Mastodon. However, most other AP platforms that I’ve tried (that I’ve expected to work) have worked.
@rokejulianlockhart To your point when you created this topic, meanwhile, https://meta.discourse.org/t/why-are-supposedly-activitypub-federated-discourse-threads-inaccessible-via-external-ap-clients/356997 cannot be found on Mastodon.
Discourse AP needs to make the url link back to the id in some way, preferably via a redirect on requests with the correct Accept content negotiation header.
Consequently, I’ll tentatively set this as a Bug. (I can’t. Too old.)
@icaria36, please comment that on the GitHub Discussion. Having someone else challenge the response lends some more credibility than having me be the liason.
Querying discourse with this results in the HTTP 400 response.
Omitting the text/html;q=0.1 returns an ActivityStreams object. So this seems to be a bug with Discourse, which seems to return a 400 anytime text/html is part of the accepted types…