When a push notification is sent, the app icon is usually displayed on the left side of the push notification, but

For example, in the case of a message app, the icon set by the sender of the message will be displayed instead of the app's icon.

It would be great if a function could be implemented to set the icon displayed on the left side of push notifications to something other than the app icon, or if the user could set the icon to an image of their choice.