SplitterWindow sash not visible on Windows

No matter what style(s) I enable, the sash is never visible. I’m using wxFormBuilder to create the UI. Everything works as expected, the only problem is the sash isn’t visible.

I can only embed one image, so I’ll add a screenshot in a reply.

Here’s the structure in wxFormBuilder:

And all mentions of the Splitter in the generated Frame code:

        self.m_splitter1 = wx.SplitterWindow( self, wx.ID_ANY, wx.DefaultPosition, wx.DefaultSize, wx.SP_3D|wx.SP_THIN_SASH )
        self.m_splitter1.SetSashGravity( 0.5 )
        self.m_splitter1.Bind( wx.EVT_IDLE, self.m_splitter1OnIdle )
        self.m_splitter1.SetMinimumPaneSize( 50 )
...
        self.m_panel1 = wx.Panel( self.m_splitter1, wx.ID_ANY, wx.DefaultPosition, wx.DefaultSize, wx.TAB_TRAVERSAL )
...
        self.m_panel2 = wx.Panel( self.m_splitter1, wx.ID_ANY, wx.DefaultPosition, wx.DefaultSize, wx.TAB_TRAVERSAL )
...
        self.m_splitter1.SplitHorizontally( self.m_panel1, self.m_panel2, 0 )
        bSizer7.Add( self.m_splitter1, 1, wx.EXPAND, 5 )
...
    def m_splitter1OnIdle( self, event ):
        self.m_splitter1.SetSashPosition( 0 )
        self.m_splitter1.Unbind( wx.EVT_IDLE )

Any suggestions on how to get the sash to be visible?

Screenshot showing the sash is there and functional, just not visible.

Unfortunately that’s now the standard on Windows. If you don’t know that there is a splitter, you’re lost…

Ah yes, “broken as designed”. Invented at IBM in the '70s but embraced by all software manufacturers over time -:frowning: