I'm running 2018.3.0b3
I can't open the Global Variable window or any of the other windows in PlayMaker, except the Playmaker Editor window. And when that's open, I'm getting this error in the console:
MissingMethodException: Method not found: 'UnityEditor.PrefabUtility.GetCorrespondingObjectFromSource'.
HutongGames.PlayMakerEditor.FsmPrefabs.DisconnectIfModifiedInstance (HutongGames.PlayMaker.Fsm fsm)
HutongGames.PlayMakerEditor.FsmEditor.CheckAllFsmPrefabInstances () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/FsmEditorSettings.cs:81)
HutongGames.PlayMakerEditor.FsmEditor.FirstUpdate () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/FsmEditorGUILayout.cs:533)
HutongGames.PlayMakerEditor.FsmEditor.Update () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/FsmEditorGUILayout.cs:562)
HutongGames.PlayMakerEditor.FsmEditorWindow.Update () (at Assets/PlayMaker/Editor/FsmEditorWindow.cs:276)
System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:222)
Rethrow as TargetInvocationException: Exception has been thrown by the target of an invocation.
System.Reflection.MonoMethod.Invoke (System.Object obj, BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MonoMethod.cs:232)
System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Reflection/MethodBase.cs:115)
UnityEditor.HostView.Invoke (System.String methodName, System.Object obj) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:342)
UnityEditor.HostView.Invoke (System.String methodName) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:336)
UnityEditor.HostView.SendUpdate () (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:438)
UnityEditor.EditorApplication.Internal_CallUpdateFunctions () (at C:/buildslave/unity/build/Editor/Mono/EditorApplication.cs:198)