Rykane

When I click "Purge Death markers" I get the following crash. Any ideas? 

Running on 64 bit Windows with 64 GB RAM 
Version: v1.12.14 (Stable)02/05/2020 19:50:27: Critical error occurred
System.ArgumentOutOfRangeException: Index was out of range. Must be non-negative and less than the size of the collection.
Parameter name: index
   at System.ThrowHelper.ThrowArgumentOutOfRangeException(ExceptionArgument argument, ExceptionResource resource)
   at VSHUD.WaypointUtilSystem.<>c__DisplayClass27_0.<PurgeWaypointsByStrings>b__0(Single dt) in E:\Games\VintageStory\ModDev\ShaderTest\Waypoint Utils\WaypointUtilSystem.cs:line 360
   at Vintagestory.Common.EventManager.TriggerGameTick(Int64 ellapsedMilliseconds, IWorldAccessor world)
   at _hLaepLRCOckdCEvZTPp1GxfgrdT._gvVdZYlJjMijmkAmKtFDCvJNXax(Single )
   at _hLaepLRCOckdCEvZTPp1GxfgrdT._nu0syyqM6QcVDRvU3XOrq03zfUh(Single )
   at _wbw3WsD1ic8cZIS5Ql2MkIqPWmb._ibkrrJqCs89QNSe99xnFzRxp3sL(Single )
   at _s54YxMQ8l5DBeihbmw81nJkPTSU._RT1lBvzfhVzcDZ6jmYewDTkUdvx(Single )
   at _s54YxMQ8l5DBeihbmw81nJkPTSU._EZIJU8BLizIQdIOGgxu5BrkHzpV(Single )
   at Vintagestory.Client.NoObf.ClientPlatformWindows.window_RenderFrame(Object sender, FrameEventArgs e)
   at System.EventHandler`1.Invoke(Object sender, TEventArgs e)
   at OpenTK.GameWindow.RaiseRenderFrame(Double elapsed, Double& timestamp)
   at OpenTK.GameWindow.DispatchRenderFrame()
   at OpenTK.GameWindow.Run(Double updates_per_second, Double frames_per_second)
   at _gilSYm6aSzOct8TKUm64HAM8OHp._tyidesQGCE1oKHv8YEo8HwYCSty(_RxGTCHor7fqeGRNMEH5pZVfBHHK , String[] )
   at _xmrDk9pogtvR6xvbzmBc2dtFsbu._tyidesQGCE1oKHv8YEo8HwYCSty(ThreadStart )
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