Create a public room without room address / room address not on the home server

Steps to reproduce

1. Click "create room" in a Matrix space
2. Make it a public room
3. Try to enter a room address for the domain of that space

alternatively

1. Create a new room
2. Make it a public room
3. Leave room address empty
4. Click "Create room"

Outcome

In the first case, the local homeserver domain of my account is hard-coded, even though I am in a space whose aliases of course use a different domain.

In the second case, the UI errors out with "please provide an address" and refuses to create the room, even though there is no technical need for that.

Given that my homeserver has a bug where it will tell me "address already in use" for every room address, and thus me being unable to create a public room, I am forced to go through the workaround with the private room instead (which is more work and more annoying).

What did you expect?

All of the following workflows should be feasible

1. Be able to create room with addresses on foreign domain names
2. Be able to create public rooms with no address, with the purpose of adding an address in a later second step (e.g. through Draupnir)

What happened instead?

I am forced to either use a bogus temporary address on my home server which I then need to delete later, or I need to create an unencrypted private room and then manually make it public afterwards.

Operating system

No response

Browser information

URL for webapp

https://app.element.io/

Application version

Element version: 1.11.100
Crypto version: Rust SDK 0.10.0 (3cc301d), Vodozemac 0.9.0

Homeserver

flausch.social

Will you send logs?

Yes

Start at the Element web app room-creation flow described in the reproduction steps, testing both creation from a Matrix space and creation with an empty room address. Done means public rooms can be created with a foreign-domain address or without an address, while preserving the existing room-creation workflows.