i have that issue as well,, sometimes it's missing results and other times i get the same result repeated on page 2. not sure why that happens, but i guess it's just a bit buggy.
Thanks, but it's not ideal for our usage, it's not selfhosted and there aren't many clients available. Plus it doesn't have unlimited message and attachments history.
You're right that XMPP is federated as well and Matrix can be non-federated but I've heard some people had trouble with the Synapse server chugging resources despite not using federation.
being korean this is pretty embarassing lol