Unfortunately, @ivory doesn't allow me to add an account from a non-Mastodon instance, even though that instance implements Mastodon-compatible APIs.
@hongminhee Unfortunately Ivory doesn't support services that use alphanumeric post ID's. Since we are based on a Twitter client, we never had to deal with that. It's something we hope to fix in the future, but it requires a lot of work in our low level code.
@ivory I understand. Thank you for explaining it!