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PreferenceObject

Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.

The PreferenceObject interface of the User Preferences API provides attributes and methods for reading and overriding user preferences.

Use the document's PreferenceManager (accessed via Navigator.preferences) to get access to the PreferenceObject objects representing each available preference.

The PreferenceManager interface inherits from EventTarget.

Instance properties

PreferenceObject.override Read only: The override value if set, null otherwise.
PreferenceObject.value Read only: The override value if set, the UA default otherwise.
PreferenceObject.validValues Read only: The valid values for the override.

Instance methods

PreferenceObject.clearOverride(): Resets any previously set override to null and fires the change event.
PreferenceObject.requestOverride(): Requests an override of the preference and fires the change event on success.

Events

change: Fired when the override is set or reset.

Specifications

Specification
Media Queries Level 5 # preference-object-interface

Browser compatibility

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This page was last modified on May 7, 2026 by MDN contributors.

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