RTC 4: Why can't I set read-only for type duration attribute in editor presentations?

Hi
I want to know why I cant set read only for duration type attributes in editor presentation? and if exist a way to do it?
I dont want that user can edit the content of the field, i know that i can set read only using the behavior operation, but still i can edit the information but i cant save, i want to know if it is possible that the user doesnt be able to edit the field?
One answer

I'm not sure why the Editor presentation dialog for this attribute type doesn't have a Read Only option like many of the others do, but you can make the presentation read only by adding a Property to the presentation of (readonly, true). Some other possible properties are identified here: https://jazz.net/library/article/130. This style (of using properties to control this) is still necessary for a variety of editor presentations in the web UI.