@pfefferle@mastodon.social just wanted to poke you about this issue again.
The latest updates to NodeBB now do a webfinger backcheck to ensure that the actor has a valid webfinger entry for their purported handle. If it does not, then the user is not properly created. Mastodon also does this. This check is probably for security as well as for preventing handle collisions.
The multilingual plugin in conjunction with the ActivityPub plugin creates users that share the same handle, and that causes issues with federated content.
For example, this article by @jonvt@vivaldi.com will load up just fine in Mastodon, but this japanese article by @akira@vivaldi.com will not, because that second article’s attributedTo is https://vivaldi.com/ja/?author=176, which fails that check (the author’s ID is actually https://vivaldi.com?author=176 as per the handle backcheck)
cc @AltCode