Bless 0.6.0 crash when save changes.

[beta-tester]

hi i am using Bless 0.6.0 unter RaspiOS (Debian Bullseye).
when i have opend multiple files in Bless, modified one file and close the Tab of the modilied file i get asked if i want to save the modified file. when i click to save changes, Bless crashes.

$ bless
Could not find a part of the path '/home/pi/.config/bless/plugins'.
Could not find a part of the path '/home/pi/.config/bless/plugins'.
Could not find a part of the path '/home/pi/.config/bless/plugins'.
Could not find file "/home/pi/.config/bless/export_patterns"
Marshaling clicked signal
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.InvalidCastException: Specified cast is not valid.
  at Bless.Gui.FileService.SaveFileInternal (Bless.Gui.DataView dv, System.String filename, System.Boolean synchronous) [0x0014e] in <f26016c40a674b7789dd9371bd25f3a1>:0 
  at Bless.Gui.FileService.SaveFile (Bless.Gui.DataView dv, System.String filename, System.Boolean forceSaveAs, System.Boolean synchronous) [0x0005f] in <f26016c40a674b7789dd9371bd25f3a1>:0 
  at Bless.Gui.FileService.AskForSaveIfFileChanged (Bless.Gui.DataView dv) [0x00041] in <f26016c40a674b7789dd9371bd25f3a1>:0 
  at Bless.Gui.FileService.CloseFile (Bless.Gui.DataView dv) [0x00011] in <f26016c40a674b7789dd9371bd25f3a1>:0 
  at Bless.Gui.DataBookTabLabel.OnCloseClicked (System.Object o, System.EventArgs args) [0x00000] in <f26016c40a674b7789dd9371bd25f3a1>:0 
  at (wrapper managed-to-native) System.Reflection.RuntimeMethodInfo.InternalInvoke(System.Reflection.RuntimeMethodInfo,object,object[],System.Exception&)
  at System.Reflection.RuntimeMethodInfo.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x0007c] in <12b418a7818c4ca0893feeaaf67f1e7f>:0 
   --- End of inner exception stack trace ---
  at System.Reflection.RuntimeMethodInfo.Invoke (System.Object obj, System.Reflection.BindingFlags invokeAttr, System.Reflection.Binder binder, System.Object[] parameters, System.Globalization.CultureInfo culture) [0x0009a] in <12b418a7818c4ca0893feeaaf67f1e7f>:0 
  at System.Reflection.MethodBase.Invoke (System.Object obj, System.Object[] parameters) [0x00000] in <12b418a7818c4ca0893feeaaf67f1e7f>:0 
  at System.Delegate.DynamicInvokeImpl (System.Object[] args) [0x0010d] in <12b418a7818c4ca0893feeaaf67f1e7f>:0 
  at System.MulticastDelegate.DynamicInvokeImpl (System.Object[] args) [0x0000b] in <12b418a7818c4ca0893feeaaf67f1e7f>:0 
  at System.Delegate.DynamicInvoke (System.Object[] args) [0x00000] in <12b418a7818c4ca0893feeaaf67f1e7f>:0 
  at GLib.Signal.ClosureInvokedCB (System.Object o, GLib.ClosureInvokedArgs args) [0x0006d] in <918680a31aa84cb89cfa7cab56ea29b8>:0 
  at GLib.SignalClosure.Invoke (GLib.ClosureInvokedArgs args) [0x0000c] in <918680a31aa84cb89cfa7cab56ea29b8>: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 <918680a31aa84cb89cfa7cab56ea29b8>:0 
  at GLib.ExceptionManager.RaiseUnhandledException (System.Exception e, System.Boolean is_terminal) [0x00000] in <918680a31aa84cb89cfa7cab56ea29b8>: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 <918680a31aa84cb89cfa7cab56ea29b8>:0 
  at Gtk.Application.gtk_main () [0x00000] in <91487213bf394f4aaf87012594abed2f>:0 
  at Gtk.Application.Run () [0x00000] in <91487213bf394f4aaf87012594abed2f>:0 
  at BlessMain..ctor (System.String[] args) [0x00000] in <e2904a26df0348ae996849b2f4e8293c>:0 
  at BlessMain.Main (System.String[] args) [0x00000] in <e2904a26df0348ae996849b2f4e8293c>:0

EDIT: Bless will not crash, when i save changes manually ([Ctrl]+[S]) and close then the tabe