Steve_Mooney, we understand wanting to have all the options on your phone work properly. We are here to help.
The Edge Lighting feature is meant to light up the edge of your phone when you get a notification that lights the screen by turning it on. If your settings are set to just show the notification, then Edge Lighting would not show on the screen.
Typically, the default Samsung Messaging app would allow Edge Lighting to work regardless. For the Message+ app,do you have Heads-Up Notification turned On? This would need to be On for it to work.
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