diff -r c89fc366bebd -r 0ffb41625592 controls/DurationCellEditor.py
--- a/controls/DurationCellEditor.py	Thu Sep 02 21:36:29 2021 +0200
+++ b/controls/DurationCellEditor.py	Thu Sep 02 22:18:14 2021 +0200
@@ -46,12 +46,12 @@
         self.Duration = wx.TextCtrl(self, size=wx.Size(0, -1),
                                     style=wx.TE_PROCESS_ENTER)
         self.Duration.Bind(wx.EVT_KEY_DOWN, self.OnDurationChar)
-        main_sizer.AddWindow(self.Duration, flag=wx.GROW)
+        main_sizer.Add(self.Duration, flag=wx.GROW)
 
         # create browse button
         self.EditButton = wx.Button(self, label='...', size=wx.Size(30, -1))
         self.Bind(wx.EVT_BUTTON, self.OnEditButtonClick, self.EditButton)
-        main_sizer.AddWindow(self.EditButton, flag=wx.GROW)
+        main_sizer.Add(self.EditButton, flag=wx.GROW)
 
         self.Bind(wx.EVT_SIZE, self.OnSize)