Guest rooms are not displayed over a federation

[EntityinArray]

Steps to reproduce

1. Open a guest room from my home server, chat history will be visible, no registration needed
   https://chat.isekai.su/#/room/!UNphPwtLKfeEyCgJqZ:isekai.su

2. Open a guest room from app.element.io, it will force you to register
   https://app.element.io/#/room/!UNphPwtLKfeEyCgJqZ:isekai.su

Outcome

What did you expect?

Ability to read chat history (and send messages as a guest, but that's a different issue)

What happened instead?

Client forces registration upon you for no reason

Operating system

Arch Linux

Browser information

Google Chrome Version 111.0.5563.64 (Official Build) unknown (64-bit)

URL for webapp

chat.isekai.su

Application version

element-v1.11.25

Homeserver

Synapse 1.79.0-1 on isekai.su

Will you send logs?

No
Sorry, I couldn't get the logs because I'm a guest and can't send /rageshake. Tell me if there is another way to obtain logs

[t3chguy]

This is peeking not working over federation, a spec issue rather than an element one. matrix-org/matrix-spec-proposals#2444