Thanks for checking this out.
It probably won't help at all but I've noticed that when I've changed color space to Linear in Unity 2018.3.6f (new project) the whole Unity 'Project Settings' window was highlighted to a very bright color for like a half of second. Then it came back to normal color.
I can also notice that one part of Unity Project Settings window (the active folded out part) is a little brighter in Linear space than in gamma. Generally it's visible that some parts of Unity UI are minimally brighter in Linear.
I'm not sure if the difference was noticeable in 2017.1.0.
I've also got this error once but I'm not sure if it could be realted and if it's harmful
NullReferenceException: Object reference not set to an instance of an object
HutongGames.PlayMakerEditor.FsmEditor.get_StateInspector () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/FsmEditor.cs:294)
HutongGames.PlayMakerEditor.InspectorPanel.Update () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/InspectorPanel.cs:106)
HutongGames.PlayMakerEditor.FsmEditor.Update () (at C:/Projects/Playmaker_1.9.0/Projects/Playmaker.source.unity/Assets/PlayMaker/Editor/Classes/FsmEditor.cs:976)
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:200)