diff --git a/src/gui/kernel/qplatformwindow.cpp b/src/gui/kernel/qplatformwindow.cpp
index d8e4e7736e..114fcf8062 100644
--- a/src/gui/kernel/qplatformwindow.cpp
+++ b/src/gui/kernel/qplatformwindow.cpp
@@ -79,7 +79,8 @@ QPlatformWindow *QPlatformWindow::parent() const
 }
 
 /*!
-    Returns the platform screen handle corresponding to this platform window.
+    Returns the platform screen handle corresponding to this platform window,
+    or null if the window is not associated with a screen.
 */
 QPlatformScreen *QPlatformWindow::screen() const
 {
diff --git a/src/gui/kernel/qwindow.cpp b/src/gui/kernel/qwindow.cpp
index 33f0409216..06db4e81fa 100644
--- a/src/gui/kernel/qwindow.cpp
+++ b/src/gui/kernel/qwindow.cpp
@@ -1678,7 +1678,7 @@ bool QWindow::setMouseGrabEnabled(bool grab)
 }
 
 /*!
-    Returns the screen on which the window is shown.
+    Returns the screen on which the window is shown, or null if there is none.
 
     For child windows, this returns the screen of the corresponding top level window.