diff --git a/src/window.rs b/src/window.rs
index 35c97e43..dca95229 100644
--- a/src/window.rs
+++ b/src/window.rs
@@ -58,7 +58,7 @@ impl WidgetImpl for PanelWindowInner {
     fn show(&self, obj: &PanelWindow) {
         self.parent_show(obj);
 
-        if let Some((display, surface)) = x::get_window_x11(&obj.upcast_ref()) {
+        if let Some((display, surface)) = x::get_window_x11(obj) {
             unsafe {
                 surface.set_skip_pager_hint(true);
                 surface.set_skip_taskbar_hint(true);
@@ -127,7 +127,7 @@ impl PanelWindow {
             return;
         };
 
-        if let Some((display, surface)) = x::get_window_x11(self.upcast_ref()) {
+        if let Some((display, surface)) = x::get_window_x11(self) {
             let top_start_x = geometry.x as x::c_ulong;
             let top_end_x = top_start_x + geometry.width as x::c_ulong - 1;
 
diff --git a/src/x.rs b/src/x.rs
index 41c51315..774386a3 100644
--- a/src/x.rs
+++ b/src/x.rs
@@ -10,10 +10,14 @@ use std::{
 
 pub use std::os::raw::{c_uchar, c_ulong, c_ushort};
 
-pub fn get_window_x11(
-    window: &gtk4::Window,
+pub fn get_window_x11<T: IsA<gtk4::Window>>(
+    window: &T,
 ) -> Option<(gdk4_x11::X11Display, gdk4_x11::X11Surface)> {
-    let surface = window.surface()?.downcast::<gdk4_x11::X11Surface>().ok()?;
+    let surface = window
+        .upcast_ref()
+        .surface()?
+        .downcast::<gdk4_x11::X11Surface>()
+        .ok()?;
     let display = surface.display()?.downcast::<gdk4_x11::X11Display>().ok()?;
     Some((display, surface))
 }