diff --git a/src/backends/x11/windowed/x11_windowed_backend.cpp b/src/backends/x11/windowed/x11_windowed_backend.cpp
index ca97beb6f8..432e887f5a 100644
--- a/src/backends/x11/windowed/x11_windowed_backend.cpp
+++ b/src/backends/x11/windowed/x11_windowed_backend.cpp
@@ -3,6 +3,7 @@
     This file is part of the KDE project.
 
     SPDX-FileCopyrightText: 2015 Martin Gräßlin <mgraesslin@kde.org>
+    SPDX-FileCopyrightText: 2023 Harald Sitter <sitter@kde.org>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
@@ -160,6 +161,7 @@ X11WindowedBackend::X11WindowedBackend(const X11WindowedBackendOptions &options)
 
 X11WindowedBackend::~X11WindowedBackend()
 {
+    destroyOutputs();
     m_pointerDevice.reset();
     m_keyboardDevice.reset();
     m_touchDevice.reset();
@@ -172,6 +174,7 @@ X11WindowedBackend::~X11WindowedBackend()
             xcb_key_symbols_free(m_keySymbols);
         }
         xcb_disconnect(m_connection);
+        m_connection = nullptr;
     }
 }
 
@@ -691,4 +694,14 @@ Outputs X11WindowedBackend::outputs() const
     return m_outputs;
 }
 
+void X11WindowedBackend::destroyOutputs()
+{
+    while (!m_outputs.isEmpty()) {
+        auto output = m_outputs.takeLast();
+        output->updateEnabled(false);
+        Q_EMIT outputRemoved(output);
+        delete output;
+    }
+}
+
 } // namespace KWin
diff --git a/src/backends/x11/windowed/x11_windowed_backend.h b/src/backends/x11/windowed/x11_windowed_backend.h
index 4d289f9f47..d82c3bf2d5 100644
--- a/src/backends/x11/windowed/x11_windowed_backend.h
+++ b/src/backends/x11/windowed/x11_windowed_backend.h
@@ -129,6 +129,7 @@ private:
     void updateSize(xcb_configure_notify_event_t *event);
     void initXInput();
     X11WindowedOutput *findOutput(xcb_window_t window) const;
+    void destroyOutputs();
 
     X11WindowedBackendOptions m_options;
     xcb_connection_t *m_connection = nullptr;