i think this message is related to this bug:
ArgumentNullException: Argument cannot be null.
Parameter name: key
System.Collections.Generic.Dictionary`2[System.Type,System.String].ContainsKey (System.Type key) (at /Users/builduser/buildslave/mono/build/mcs/class/corlib/System.Collections.Generic/Dictionary.cs:458)
HutongGames.PlayMakerEditor.VariableTypeMenu.IsTypeAliased (System.Type type) (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/FsmPrefabs.cs:669)
HutongGames.PlayMakerEditor.FsmObjectEditor.DoTypeSelector () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/BugReportWindow.cs:119)
HutongGames.PlayMakerEditor.FsmVariablesEditor.EditVariableValue () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/ActionEditor.cs:301)
HutongGames.PlayMakerEditor.FsmVariablesEditor.DoVariableEditor () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/ActionEditor.cs:267)
HutongGames.PlayMakerEditor.FsmVariablesEditor.OnGUI () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/GlobalVariablesWindow.cs:132)
HutongGames.PlayMakerEditor.GlobalVariablesWindow.DoGUI () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/ActionEditor.cs:3112)
HutongGames.PlayMakerEditor.BaseEditorWindow.OnGUI () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/CanvasView.cs:605)
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:295)
UnityEditor.HostView.Invoke (System.String methodName) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:288)
UnityEditor.HostView.InvokeOnGUI (Rect onGUIPosition) (at C:/buildslave/unity/build/Editor/Mono/HostView.cs:255)
UnityEngine.GUIUtility:ProcessEvent(Int32, IntPtr)
i restarted unity bug the bug is still there