void wxSplitterWindow::OnPaint(wxPaintEvent& WXUNUSED(event))
{
wxPaintDC dc(this);
+#ifdef __WXOSX__
+ // as subpanels might have a transparent background we must erase the background
+ // at least on OSX, otherwise traces of the sash will remain
+ // test with: splitter sample->replace right window
+ dc.Clear();
+#endif
DrawSash(dc);
}