We're using the latest package of the Unity AndroidPushPlugin (Android 7.0+ Plugin Fixes (#188)).
We've added an "app_icon.png" and an "app_icon_transparent.png" in the res/drawable folder in Unity's Android plugin folder, but it appears that only the _transparent variant is used for both icons in the notification area of Android (large and small):
On the left you can see the result in the notification area (the white L is barely visible), on the right the actual _transparent.png (except the gray background of course) (the app_icon.png is totally different and colored and is not visible in the notification area).
It is possible to use two different icons just like other Android apps do (like WhatsApp)? We'd like to use the regular app icon as the large and a white-only small one.