The unregister() method of the RegisteredUserScript object unregisters the user scripts represented by the object, user scripts that were registered using  userScripts.register().

Note: User Scripts are automatically unregistered when the related extension page (from which the user scripts were registered) is unloaded, so you should register a user script from an extension page that persists at least as long as you want the user scripts to stay registered.


const registeredUserScript = await browser.userScripts.register(
  userScriptOptions       // object
await registeredUserScript.unregister()



Return value

A Promise that is resolved once the user scripts are unregistered. The promise does not return a value.

Browser compatibility

Update compatibility data on GitHub
ChromeEdgeFirefoxOperaFirefox for Android
unregisterChrome No support NoEdge No support NoFirefox Full support 68
Full support 68
Full support 66
Disabled From version 66: this feature is behind the extensions.webextensions.userScripts.enabled preference (needs to be set to true). To change preferences in Firefox, visit about:config.
Opera No support NoFirefox Android Full support 68


Full support  
Full support
No support  
No support
User must explicitly enable this feature.
User must explicitly enable this feature.

See also