How do I preserve Lightmaps when loading additive scenes in Unity5

I am trying to load a scene that is lightmapped into another additively, when I do the objects in the additive scene are no longer lightmapped. All the lights that are set to baked start rendering as real-time.

What little documentation I could find said that it should work fine.

Turns out it is a bug:

Unity bug tracker
Forum post

I think the only way to fix this is to Vote for the bug, I am surprised that there is so few votes on it so far.

If anyone manages to get a fix please share, at the moment my only options are to go through all of my scenes and strip every light or push the minimum requirements up to that of a supercomputer.

A way to avoid that : GameObject.DontDestroyOnLoad + Application.LoadLevelAsync :stuck_out_tongue:
Works well.