I checked, there is no duplicate and I use ecosystem.
It seems to be a conflict with the array maker actions, because AnyKeyString works in a different project where arraymaker is not installed.
I receive this message once AnyKeyString is installed:
Assets/PlayMaker Custom Actions/ArrayMaker/PlayerPrefsxGetArrayList.cs(233,63): error CS0103: The name `PlayerPrefsX' does not exist in the current context
NullReferenceException: Object reference not set to an instance of an object
UnityEngine.UI.Graphic.OnRebuildRequested () (at C:/buildslave/unity/build/Extensions/guisystem/UnityEngine.UI/UI/Core/Graphic.cs:480)
UnityEngine.UI.GraphicRebuildTracker.OnRebuildRequested () (at C:/buildslave/unity/build/Extensions/guisystem/UnityEngine.UI/UI/Core/GraphicRebuildTracker.cs:33)
UnityEngine.CanvasRenderer.RequestRefresh () (at C:/buildslave/unity/build/artifacts/generated/common/modules/UI/CanvasRendererBindings.gen.cs:314)