Allow ServiceWorker to control srcdoc iframes

Supported on: Microsoft Edge version 134, Windows 7 or later

Registry

HKLM Software\Policies\Microsoft\Edge

HKCU Software\Policies\Microsoft\Edge

Value name: ServiceWorkerToControlSrcdocIframeEnabled

Enabled: ServiceWorkerToControlSrcdocIframeEnabled = 1

Disabled: ServiceWorkerToControlSrcdocIframeEnabled = 0

Description

https://github.com/w3c/ServiceWorker/issues/765 asks srcdoc iframe with the "allow-same-origin" sandbox attribute to be under ServiceWorker control. By default (if left unset) or when set to Enabled, Microsoft Edge makes srcdoc iframes with "allow-same-origin" sandbox attributes to be under ServiceWorker control. Setting the policy to Disabled prevents ServiceWorker control over srcdoc iframes. This policy is temporary and planned for deprecation in 2026.