The read-only priority property of the TaskSignal interface indicates the signal priority.

The initial value is set in the associated TaskController by specifying it as an argument to the TaskController constructor (by default it is "user-visible"). The priority of the signal can be changed by calling TaskController.setPriority() on the associated controller.

For tasks with a mutable priority, this value is used to set the initial task priority and later to change it. Tasks with an immutable priority will ignore the value.

A string indicating the signal priority. This will be one of: "user-blocking", "user-visible", "background".

The priority is most commonly used by developers to determine the new priority following prioritychange events. See TaskSignal: prioritychange event for a live example.