I got both playmaker and facebook (via Soomla Profile) implemented in my scene.
When I get a login panel from facebook and then I close it, this nefarious error appears in Console repeatedly (every frame?):
{NullReferenceException: Object reference not set to an instance of an object
UnityEngine.GUI.CallWindowDelegate (UnityEngine.WindowFunction func, Int32 id, UnityEngine.GUISkin _skin, Int32 forceRect, Single width, Single height, UnityEngine.GUIStyle style) (at C:/buildslave/unity/build/artifacts/generated/common/runtime/GUIBindings.gen.cs:1458)}
By trial and error I found out that it stops when the PlayMakerGUI script is disabled it stops happening.
Anyone knows how to fix this?