Unfortunately, In order to limit a particular user to just the web interface (and not allow them on devices). One must enable access from all devices in order to allow this.
It would be good to have a generic item in devices that represents web browsers generically. This would allow control over the web browser interface! Limiting users to just the webpage....
For example, I have a user who I want to just have permission to download raw files. At present I need to enable there access from all devices else they can't access the web page. I don't want them to use or have permission to use any emby app or device except the web interface.
Having a generic device that represents the web interface would allow control...