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This API is available on Firefox OS for internal applications only.


The isExplicit method allows to know if the setting is explicit (true) or implicit (false).

Depending on the privileges of the applications, some permissions are implicit. If for some reason the application tries to change permission for an implicit one, an error will be thrown. In order to avoid such errors, it's possible to check if the permission is explicit with this method.


 var value = navigator.mozPermissionsettings.isExplicit(permission, manifest, origin, browserFlag)


A string with the name of the permission to retrieve.
A string representing the URL of the manifest of the app to check, or for an app running inside the browser, the URL of the browser app manifest.
A string representing the domain name of the app.
A boolean indicating if the app is running in the browser instead of as an installed app.


A boolean indicating if the permission is explicit (true) or implicit (false)


Not part of any specification.

See also

Document Tags and Contributors

 Contributors to this page: chrisdavidmills, teoli, kscarfone, Jeremie
 Last updated by: chrisdavidmills,