Do not set window.opener for links targeting _blank

If you enable this policy or leave it unset, the window.opener property is set to null unless the anchor specifies rel="opener".

If you disable this policy, popups that target _blank are permitted to access (via JavaScript) the page that requested to open the popup.

This policy will be obsoleted in Microsoft Edge version 95.

Supported on: Microsoft Edge version 88, Windows 7 or later

Registry HiveHKEY_LOCAL_MACHINE or HKEY_CURRENT_USER
Registry PathSoftware\Policies\Microsoft\Edge
Value NameTargetBlankImpliesNoOpener
Value TypeREG_DWORD
Enabled Value1
Disabled Value0

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