diff --git a/panels/dock/x11dockhelper.cpp b/panels/dock/x11dockhelper.cpp
index b4981b554..a13de2612 100644
--- a/panels/dock/x11dockhelper.cpp
+++ b/panels/dock/x11dockhelper.cpp
@@ -403,14 +403,19 @@ void X11DockHelper::onWindowClientListChanged()
             onWindowAdded(window);
         }
     }
+    bool mightNeedRecheckDockOverlap = false;
     for (auto it = m_windows.cbegin(); it != m_windows.cend();) {
         if (!windows.contains(it.key())) {
             delete it.value();
             it = m_windows.erase(it);
+            mightNeedRecheckDockOverlap = true;
         } else {
             it++;
         }
     }
+    if (mightNeedRecheckDockOverlap) {
+        Q_EMIT isWindowOverlapChanged(isWindowOverlap());
+    }
 }
 
 void X11DockHelper::onWindowAdded(xcb_window_t window)