Why is there No Edge Lighting on S8/S8+ when there are notifications from WhatsApp?

In case of some 3’rd party applications, you need to set related option within application by itself.

Please check the settings in WhatsApp as following steps: WhatsApp -> Settings -> Notifications -> Popup notification

If current selection is "No popup“, please change to "Always show popup“

If you still have problem to get notification from WhatsApp after the above setting, please check if "WhatsApp" is selected in Notifications of settings.

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