I think this might be a bug, but it's very irregular and I can't quite nail it down.
I have a number of prefabs with macro flow graphs on them. All have a variety of object variables saved on them as part of the prefab. If I add a new object variable to the prefab while it's in a scene, set its type and value, and go into play, the variable type and value reset to null.
If, however, I update the prefab with the new variable before entering play mode, then it works fine and the variable transfers into play no problem.
Note, this doesn't seem to happen every time. Sometimes it's okay and doesn't require that I update the prefab for it to transition to play mode. Also, it seems to happen more often with certain types: Audio Clip in particular.
Currently on Bolt 1.2.3 and Unity 2017.3.0f3
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