The HTMLVideoElement textTracks / TextTrackList, audioTracks / AudioTrackList ,videoTracks / VideoTrackList are not iterable.
This is a regression comparing to the dart:html directive.

https://api.flutter.dev/flutter/dart-html/TextTrackList-class.html
https://pub.dev/documentation/web/latest/web/TextTrackList-extension-type.html

The consequence is, that we cannot return a list of available tracks, as the list is basically not accessible.
The method getTrackById is only searching the tracks by their DOM id (as far as I understood).

All these track lists should implement some form of iterable.