2D viewport instance inside a 3D scene visible in editor but blank in game

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:bust_in_silhouette: Asked By dodgyville


I have created a 3D scene with a viewport containing a GUI Control with some labels (to have 2D text floating in 3D world like a billboard). It shows perfectly in its own 3D Scene.

In my larger 3D world scene I instance the billboard and it shows up in the world and works and the labels show correctly.

However, when I run the game, the viewport is totally black.

Would be grateful for any suggestions on what the problem might be. I think it might be something to do with the camera in the 3D world.