diff --git a/abstract_client.h b/abstract_client.h
--- a/abstract_client.h
+++ b/abstract_client.h
@@ -817,6 +817,14 @@
      **/
     virtual Group *group();
 
+    /**
+     * Returns whether this is an internal client.
+     *
+     * Internal clients are created by KWin and used for special purpose windows,
+     * like the task switcher, etc.
+     **/
+    virtual bool isInternal() const;
+
 public Q_SLOTS:
     virtual void closeWindow() = 0;
 
diff --git a/abstract_client.cpp b/abstract_client.cpp
--- a/abstract_client.cpp
+++ b/abstract_client.cpp
@@ -353,6 +353,8 @@
     // and the docks move into the NotificationLayer (which is between Above- and
     // ActiveLayer, so that active fullscreen windows will still cover everything)
     // Since the desktop is also activated, nothing should be in the ActiveLayer, though
+    if (isInternal())
+        return UnmanagedLayer;
     if (isDesktop())
         return workspace()->showingDesktop() ? AboveLayer : DesktopLayer;
     if (isSplash())          // no damn annoying splashscreens
@@ -2080,4 +2082,9 @@
     return nullptr;
 }
 
+bool AbstractClient::isInternal() const
+{
+    return false;
+}
+
 }
diff --git a/shell_client.h b/shell_client.h
--- a/shell_client.h
+++ b/shell_client.h
@@ -122,7 +122,6 @@
      **/
     pid_t pid() const override;
 
-    virtual bool isInternal() const;
     bool isLockScreen() const override;
     bool isInputMethod() const override;
     virtual QWindow *internalWindow() const;
diff --git a/shell_client.cpp b/shell_client.cpp
--- a/shell_client.cpp
+++ b/shell_client.cpp
@@ -1083,11 +1083,6 @@
     return surface()->client()->processId();
 }
 
-bool ShellClient::isInternal() const
-{
-    return false;
-}
-
 bool ShellClient::isLockScreen() const
 {
     return surface()->client() == waylandServer()->screenLockerClientConnection();