magnetometer library Null safety
The interface of the Sensor APIs provides information about the
magnetic field as detected by the device's primary magnetometer
To use this sensor, the user must grant permission to the
'magnetometer'device sensor through the Permissions API. If a feature policy blocks use of a feature, it's because your code is inconsistent with the policies set on your server. This is not something that would ever be shown to a user. The
Feature-PolicyHTTP header article contains implementation instructions.