1. Dart
2. dart:html
3. ExtendableMessageEvent
4. ports property

ExtendableMessageEvent class

1. Properties
2. bubbles
3. cancelable
4. composed
5. currentTarget
6. data
7. defaultPrevented
8. eventPhase
9. hashCode
10. isTrusted
11. lastEventId
12. matchingTarget
13. origin
14. path
15. ports
16. runtimeType
17. source
18. target
19. timeStamp
20. type
21. Methods
22. composedPath
23. noSuchMethod
24. preventDefault
25. stopImmediatePropagation
26. stopPropagation
27. toString
28. waitUntil
29. Operators
30. operator ==

List<MessagePort> get ports native;