Optional
getOptional
isFunction to check if this object extension is compatible with the given object. If not compatible, the object extension will not be added to the object. This is only checked when the extension is registered.
The extension is assumed to be compatible if this function is not defined
Optional
onFunction to be called when the object the extension is added on the object. This generally happens when either the object is registered or extnsion is added
Function to return the UI config for this material extension. This is called once when the material extension is registered.