Under the Roles & Permissions tab selecting Custom level in any dropdown is never saved, if it was it would be impossible to ever return to another dropdown option as it gets replaced by the number input

### Steps to reproduce

1. Open a room you created
2. Open the room its information 
3. Click the room settings button
4. In the settings open tab Roles & Permissions
5. Select Custom level in any dropdown

### Outcome

Expected: The number input is revealed below the dropdown when this choice is selected

Actual: The number input replaces the dropdown, causing not being able to revert to another option. Currently Custom level does not seem to get saved so on reopening the tab dropdown is in place again instead.

### Operating system

macOS

### Browser information

Chrome

### URL for webapp

_No response_

### Application version

_No response_

### Homeserver

_No response_

### Will you send logs?

No