read_only_user_attributes documentation not correct

The RH-SSO 7.6 docuemtation states you can configure read_only_user_attributes by add this configuration to your standalone(-*).xml files to the configuration of the Red Hat Single Sign-On server subsystem:

~~~
<spi name="userProfile">
    <provider name="legacy-user-profile" enabled="true">
        <properties>
            <property name="read-only-attributes" value="["foo","bar*"]"/>
            <property name="admin-read-only-attributes" value="["foo"]"/>
        </properties>
    </provider>
</spi>
~~~

The same can be configured with the usage of the JBoss CLI with the commands:

~~~
/subsystem=keycloak-server/spi=userProfile/:add
/subsystem=keycloak-server/spi=userProfile/provider=legacy-user-profile/:add(properties={},enabled=true)
/subsystem=keycloak-server/spi=userProfile/provider=legacy-user-profile/:map-put(name=properties,key=read-only-attributes,value=[foo,bar*])
/subsystem=keycloak-server/spi=userProfile/provider=legacy-user-profile/:map-put(name=properties,key=admin-read-only-attributes,value=[foo])
~~~

However, the only way to set the read-only attribute is to use the declarative-user-profile which is still in Technology Preview

1) Started RH-SSO with the declarative user profile enabled

~~~
./standalone.sh -Dkeycloak.profile.feature.declarative_user_profile=enabled
~~~

2) Ran the below command via the JBoss CLI modifying the user profile provider to use: declarative-user-profile 

~~~
/subsystem=keycloak-server/spi=userProfile/:add
/subsystem=keycloak-server/spi=userProfile/provider=declarative-user-profile/:add(properties={},enabled=true)
/subsystem=keycloak-server/spi=userProfile/provider=declarative-user-profile/:map-put(name=properties,key=read-only-attributes,value=[email])
~~~

3) Logged into the account client and when i tried to change the email i got the following error:

~~~
Console error: Update of read-only attribute rejected
~~~

~~~
Log error: 19:20:52,275 WARN  [org.keycloak.userprofile.validator.ReadOnlyAttributeUnchangedValidator] (default task-1) Attempt to edit denied attribute '(?i:^\Qemail\E$)' of user 'user1'
~~~

[1] https://access.redhat.com/documentation/en-us/red_hat_single_sign-on/7.6/html-single/server_administration_guide/index#read_only_user_attributes