The KeyboardEvent.code property represents a physical key on the keyboard (as opposed to the character generated by pressing the key). In other words, this property returns a value which isn't altered by keyboard layout or the state of the modifier keys.
The KeyboardEvent.metaKey read-only property returning a Boolean that indicates if the Meta key was pressed (true) or not (false) when the event occurred. Some operating systems may intercept the key so it is never detected.
The MediaStreamTrack.enabled property returns a Boolean with a value of true if the track is enabled, that is allowed to render the media source stream; or false if it is disabled, that is not rendering the media source stream but silence and blackness. If the track has been disconnected, this value can be changed but has no effect.