Computer Configuration > Administrative Templates > Microsoft Edge
Both
HKLM\Software\Policies\Microsoft\Edge
Controls the duration (in seconds) that keepalive requests are allowed to prevent the browser from completing its shutdown. If you configure this policy, the browser will block completing shutdown while it processes any outstanding keepalive requests (see https://fetch.spec.whatwg.org/#request-keepalive-flag) up to the maximum period of time specified by this policy. If you disable or don't configure this policy, the default value of 0 seconds is used and outstanding keepalive requests will be immediately cancelled during browser shutdown.