The MediaKeySession.keyStatuses read-only property returns a reference to a read-only MediaKeyStatusMap of the current session's keys and their statuses.
The MediaKeySession.sessionId read-only property contains a unique string generated by the CDM for the current media object and its associated keys or licenses.
The MediaKeySystemAccess.getConfiguration() method returns a MediaKeySystemConfiguration object with the supported combination of configuration options.
The MediaKeySystemConfiguration.initDataTypes read-only property returns a list of supported initialization data type names. An initialization data type is a string indicating the format of the initialization data.