A `DOMString` which uniquely identifies the track within the media. This ID can be used to locate a specific track within an audio track list by calling `AudioTrackList.getTrackById()`. The ID can also be used as the fragment part of the URL if the media supports seeking by media fragment per the Media Fragments URI specification.
A `Blob` representing the data associated with the event. The event was fired on the `EventTarget` because of something happening on that specific `Blob`.
Is a `Boolean` indicating whether or not the control should have input focus when the page loads, unless the user overrides it, for example by typing in a different control. Only one form-associated element in a document can have this attribute specified.
If this style sheet is imported into the document using an `@import` rule, the `ownerRule` property will return that `CSSImportRule`, otherwise it returns `null`.
Is a positive `integer` reflecting the `width` HTML attribute of the `canvas` element interpreted in CSS pixels. When the attribute is not specified, or if it is set to an invalid value, like a negative, the default value of `300` is used.
Adds a new stop, defined by an `offset` and a `color`, to the gradient. If the offset is not between `0` and `1` an `INDEX_SIZE_ERR` is raised, if the color can't be parsed as a CSS `color`, a `SYNTAX_ERR` is raised.
Returns the characters generated by the input method that raised the event; its varies depending on the type of event that generated the `CompositionEvent` object.
Returns an enumerated value representing the type of the key, a secret key (for symmetric algorithm), a public or a private key (for an asymmetric algorithm)