2017.20f2 with ch.sycoforge error

When I build the player (win) I get :

NullReferenceException: Object reference not set to an instance of an object
ch.sycoforge.Unity.Editor.Versioning.VersionTracker.IncrementBuild ()
ch.sycoforge.Unity.Editor.Versioning.VersionTracker.OnPostProcessBuild (BuildTarget target, System.String buildPath)
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.Build.BuildPipelineInterfaces+AttributeCallbackWrapper.OnPostprocessBuild (BuildTarget target, System.String path) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/BuildPipelineInterfaces.cs:86)
UnityEditor.Build.BuildPipelineInterfaces.OnBuildPostProcess (BuildTarget platform, System.String path, Boolean strict) (at C:/buildslave/unity/build/Editor/Mono/BuildPipeline/BuildPipelineInterfaces.cs:324)
UnityEngine.GUIUtilityrocessEvent(Int32, IntPtr)

then

Error building Player: NullReferenceException: Object reference not set to an instance of an object

I have no idea what this one is going on about. Possibly related to the above.

It seems to actually builds, but then it says :

Build completed with a result of 'Failed'
UnityEngine.GUIUtilityrocessEvent(Int32, IntPtr)

UnityEditor.BuildPlayerWindow+BuildMethodException: 2 errors
at UnityEditor.BuildPlayerWindow+DefaultBuildMethods.BuildPlayer (BuildPlayerOptions options) [0x00207] in C:\buildslave\unity\build\Editor\Mono\BuildPlayerWindowBuildMethods.cs:172
at UnityEditor.BuildPlayerWindow.CallBuildMethods (Boolean askForBuildLocation, BuildOptions defaultBuildOptions) [0x00050] in C:\buildslave\unity\build\Editor\Mono\BuildPlayerWindowBuildMethods.cs:83
UnityEngine.GUIUtilityrocessEvent(Int32, IntPtr)

Any ideas?

 

I wish I can make minimal reproduction case.. This is not going to be easy.. And yes, it used to build fine on my previous Unity version 5.6.3p3..

 

According to Google, several packages of the following publisher contain a "ch.sycoforge" DLL:
https://www.assetstore.unity3d.com/en/#!/search/page=1/sortby=popularity/query=publisher:9267

Do you have installed any of these assets? Perhaps you can reproduce the issue by just adding such package to a new project?