Clicking on Preferences in menu causes crash on Ubuntu 17.04 64 bit

[ce3a]

Running from a terminal (/usr/bin/indicator-stocks) and then clicking on Preferences yields:

Exception in Gtk# callback delegate
  Note: Applications can use GLib.ExceptionManager.UnhandledException to handle the exception.
System.Reflection.TargetInvocationException: Exception has been thrown by the target of an invocation. ---> System.NullReferenceException: Object reference not set to an instance of an object
  at indicatorstocks.PreferencesDialog..ctor () [0x000be] in <8434de6d43f04e3595d4d4e589b2bd3a>:0 
  at indicatorstocks.Indicator.OnPrefs (System.Object sender, System.EventArgs args) [0x00000] in <8434de6d43f04e3595d4d4e589b2bd3a>:0 
  at (wrapper managed-to-native) System.Reflection.MonoMethod:InternalInvoke (System.Reflection.MonoMethod,object,object[],System.Exception&)
  at System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00038] in <8f2c484307284b51944a1a13a14c0266>:0 
   --- End of inner exception stack trace ---
  at System.Reflection.MonoMethod.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x00053] in <8f2c484307284b51944a1a13a14c0266>:0 
  at System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) [0x00000] in <8f2c484307284b51944a1a13a14c0266>:0 
  at System.Delegate.DynamicInvokeImpl (System.Object[] args) [0x0010d] in <8f2c484307284b51944a1a13a14c0266>:0 
  at System.MulticastDelegate.DynamicInvokeImpl (System.Object[] args) [0x0000b] in <8f2c484307284b51944a1a13a14c0266>:0 
  at System.Delegate.DynamicInvoke (System.Object[] args) [0x00000] in <8f2c484307284b51944a1a13a14c0266>:0 
  at GLib.Signal.ClosureInvokedCB (System.Object o, GLib.ClosureInvokedArgs args) [0x0006d] in <5a439e0caae7469886e7119d9f6bc621>:0 
  at GLib.SignalClosure.Invoke (GLib.ClosureInvokedArgs args) [0x0000c] in <5a439e0caae7469886e7119d9f6bc621>:0 
  at GLib.SignalClosure.MarshalCallback (System.IntPtr raw_closure, System.IntPtr return_val, System.UInt32 n_param_vals, System.IntPtr param_values, System.IntPtr invocation_hint, System.IntPtr marshal_data) [0x0006c] in <5a439e0caae7469886e7119d9f6bc621>:0 
  at GLib.ExceptionManager.RaiseUnhandledException (System.Exception e, System.Boolean is_terminal) [0x00000] in <5a439e0caae7469886e7119d9f6bc621>:0 
  at GLib.SignalClosure.MarshalCallback (System.IntPtr raw_closure, System.IntPtr return_val, System.UInt32 n_param_vals, System.IntPtr param_values, System.IntPtr invocation_hint, System.IntPtr marshal_data) [0x00000] in <5a439e0caae7469886e7119d9f6bc621>:0 
  at Gtk.Application.gtk_main () [0x00000] in <573b897a54ae4730b20442c8cd3b9a43>:0 
  at Gtk.Application.Run () [0x00000] in <573b897a54ae4730b20442c8cd3b9a43>:0 
  at indicatorstocks.IndicatorStocks.Main (System.String[] args) [0x00000] in <8434de6d43f04e3595d4d4e589b2bd3a>:0 

[ce3a]

It is gtk-sharp Bug 51688 - NodeView.NodeStore setter not changing underlying field.

[ce3a]

Related: Bug 33448 - NodeStore not usable as TreeModel.