from the console, after trying to open a project:

$ monodevelop 

(MonoDevelop:7446): Gtk-CRITICAL **: gtk_container_foreach: assertion `GTK_IS_CONTAINER (container)' failed

(MonoDevelop:7446): Gtk-CRITICAL **: gtk_container_foreach: assertion `GTK_IS_CONTAINER (container)' failed
7993 [-1226945648] INFO MonoDevelop.Core.ILoggingService (null) - Initializing service: MonoDevelop.Core.PropertyService
8416 [-1226945648] INFO MonoDevelop.Core.ILoggingService (null) - Loaded add-in: MonoDevelop.Core
8458 [-1226945648] INFO MonoDevelop.Core.ILoggingService (null) - Loaded add-in: MonoDevelop.Projects
8464 [-1226945648] INFO MonoDevelop.Core.ILoggingService (null) - Loaded add-in: MonoDevelop.Documentation
8539 [-1226945648] INFO MonoDevelop.Core.ILoggingService (null) - Initializing service: MonoDevelop.Core.SystemAssemblyService
9430 [-1226945648] DEBUG MonoDevelop.Core.ILoggingService (null) - Reading /home/bugabundo/.config/MonoDevelop/CodeCompletionData/mscorlib_2.0.0.0_b77a5c561934e089.pidb
10266 [-1226945648] INFO MonoDevelop.Core.ILoggingService (null) - Initializing service: MonoDevelop.Projects.Documentation.IDocumentationService
25627 [-1226945648] DEBUG MonoDevelop.Core.ILoggingService (null) - Writing /home/bugabundo/.config/MonoDevelop/CodeCompletionData/mscorlib_1.0.5000.0_b77a5c561934e089.pidb

(MonoDevelop:7446): Gtk-CRITICAL **: gtk_object_destroy: assertion `object != NULL' failed
Exception in Gtk# callback delegate
  Note: Applications can use GLib.ExceptionManager.UnhandledException to handle the exception.
GLib.MissingIntPtrCtorException: GLib.Object subclass MonoDevelop.Ide.Gui.Dialogs.FileSelectorDialog must provide a protected or public IntPtr ctor to support wrapping of native object handles.
  at GLib.ObjectManager.CreateObject (IntPtr raw) [0x00000] 
  at GLib.Object.GetObject (IntPtr o, Boolean owned_ref) [0x00000] 
  at GLib.ListBase.DataMarshal (IntPtr data) [0x00000] 
  at GLib.ListBase+ListEnumerator.get_Current () [0x00000] 
  at GLib.ListBase.CopyTo (System.Array array, Int32 index) [0x00000] 
  at GLib.Marshaller.ListToArray (GLib.ListBase list, System.Type type) [0x00000] 
  at Gtk.Window.ListToplevels () [0x00000] 
  at MonoDevelop.Components.Commands.CommandManager.GetActiveWidget (Gtk.Window win) [0x00000] 
  at MonoDevelop.Components.Commands.CommandManager.UpdateToolbars () [0x00000] 
  at MonoDevelop.Components.Commands.CommandManager.UpdateStatus () [0x00000] 
  at (wrapper delegate-invoke) System.MulticastDelegate:invoke_bool ()
  at GLib.Timeout+TimeoutProxy.Handler () [0x00000] 

   at GLib.ExceptionManager.RaiseUnhandledException ()
   at GLib.Timeout+TimeoutProxy.Handler ()
   at GLib.Timeout+TimeoutProxy.Handler ()
   at Gtk.Application.gtk_main ()
   at Gtk.Application.gtk_main ()
   at Gtk.Application.Run ()
   at MonoDevelop.Ide.Gui.IdeApp.Run ()
   at MonoDevelop.Ide.Gui.IdeStartup.Run ()
   at MonoDevelop.Core.AddIns.AddInService.StartApplication ()
   at MonoDevelop.Startup.SharpDevelopMain.Main ()

Unhandled Exception: System.InvalidOperationException: Operation is not valid due to the current state of the object
  at System.Collections.Queue.Dequeue () [0x00000] 
  at BooBinding.Gui.BooShellModel.ThreadRun () [0x00000] 
  at (wrapper delegate-invoke) System.MulticastDelegate:invoke_void ()
Exception in Gtk# callback delegate
  Note: Applications can use GLib.ExceptionManager.UnhandledException to handle the exception.
System.Threading.ThreadAbortException: Thread was being aborted
  at <0x00000> <unknown method>
  at (wrapper managed-to-native) System.Object:__icall_wrapper_mono_thread_interruption_checkpoint ()
  at (wrapper managed-to-native) System.Threading.Thread:Sleep_internal (int)
  at System.Threading.Thread.Sleep (Int32 millisecondsTimeout) [0x00000] 
  at BooBinding.BooShell.BooShell.ProcessCommands () [0x00000] 
  at (wrapper delegate-invoke) System.MulticastDelegate:invoke_bool ()
  at GLib.Idle+IdleProxy.Handler () [0x00000] 

   at GLib.ExceptionManager.RaiseUnhandledException ()
   at GLib.Idle+IdleProxy.Handler ()
   at GLib.Idle+IdleProxy.Handler ()
   at Gtk.Application.gtk_main ()
   at Gtk.Application.gtk_main ()
   at Gtk.Application.Run ()
   at BooBinding.BooShell.BooShell.ThreadRun ()
   at System.MulticastDelegate.invoke_void ()
Segmentation fault (core dumped)