diff --git a/tests/gtk/test_window.py b/tests/gtk/test_window.py
index f5fd522..82a6d6a 100644
--- a/tests/gtk/test_window.py
+++ b/tests/gtk/test_window.py
@@ -82,6 +82,18 @@ class TestWindow(unittest.TestCase):
         self.assertEqual(window2.child, label)
         self.assertEqual(window2._splitview.props.content, label)
 
+    def test_sidebar(self):
+        """Test the window sidebar property."""
+        self.assertIsNone(self.window.sidebar)
+        self.window.sidebar = Gtk.Label()
+        self.assertEqual(self.window._splitview.props.sidebar,
+                         self.window.sidebar)
+
+        label = Gtk.Label()
+        window2 = xfstestsdb.gtk.window.Window(sidebar=label)
+        self.assertEqual(window2.sidebar, label)
+        self.assertEqual(window2._splitview.props.sidebar, label)
+
     def test_runid(self):
         """Test the window runid property."""
         self.assertEqual(self.window.runid, 0)
diff --git a/xfstestsdb/gtk/window.py b/xfstestsdb/gtk/window.py
index 9830f2e..d4c6609 100644
--- a/xfstestsdb/gtk/window.py
+++ b/xfstestsdb/gtk/window.py
@@ -10,6 +10,7 @@ class Window(Adw.Window):
     """Our customized Window displayed to the user."""
 
     child = GObject.Property(type=Gtk.Widget)
+    sidebar = GObject.Property(type=Gtk.Widget)
     headerbar = GObject.Property(type=Adw.HeaderBar)
     title = GObject.Property(type=Adw.WindowTitle)
     runid = GObject.Property(type=int)
@@ -22,6 +23,7 @@ class Window(Adw.Window):
                          title=Adw.WindowTitle(title="xfstestsdb gtk"),
                          headerbar=Adw.HeaderBar(), **kwargs)
         self._splitview = Adw.OverlaySplitView(content=self.child,
+                                               sidebar=self.sidebar,
                                                collapsed=True,
                                                show_sidebar=self.show_sidebar)
         self._show_sidebar = Gtk.ToggleButton(icon_name="sidebar-show",
@@ -37,6 +39,7 @@ class Window(Adw.Window):
         self._show_sidebar.bind_property("active", self, "show-sidebar",
                                          GObject.BindingFlags.BIDIRECTIONAL)
         self.bind_property("show-sidebar", self._splitview, "show-sidebar")
+        self.bind_property("sidebar", self._splitview, "sidebar")
         self.bind_property("child", self._splitview, "content")
 
         self.connect("notify::runid", self.__notify_runid)