diff --git a/autotests/integration/internal_window.cpp b/autotests/integration/internal_window.cpp
index 0830452087..bacdc2030a 100644
--- a/autotests/integration/internal_window.cpp
+++ b/autotests/integration/internal_window.cpp
@@ -33,6 +33,8 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #include <KWayland/Client/seat.h>
 #include <KWayland/Client/shell.h>
 
+#include <KWayland/Server/surface_interface.h>
+
 #include <linux/input.h>
 
 using namespace KWayland::Client;
@@ -64,6 +66,7 @@ private Q_SLOTS:
     void testModifierClickUnrestrictedMove();
     void testModifierScroll();
     void testPopup();
+    void testScale();
 };
 
 class HelperWindow : public QRasterWindow
@@ -687,6 +690,29 @@ void InternalWindowTest::testPopup()
     QCOMPARE(internalClient->isPopupWindow(), true);
 }
 
+void InternalWindowTest::testScale()
+{
+    QMetaObject::invokeMethod(kwinApp()->platform(), "setVirtualOutputs", Qt::DirectConnection,
+        Q_ARG(int, 2),
+        Q_ARG(QVector<QRect>, QVector<QRect>({QRect(0,0,1280, 1024), QRect(1280/2, 0, 1280, 1024)})),
+        Q_ARG(QVector<int>, QVector<int>({2,2})));
+
+    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
+    QVERIFY(clientAddedSpy.isValid());
+    HelperWindow win;
+    win.setGeometry(0, 0, 100, 100);
+    win.setFlags(win.flags() | Qt::Popup);
+    win.show();
+    QCOMPARE(win.devicePixelRatio(), 2.0);
+    QVERIFY(clientAddedSpy.wait());
+    QCOMPARE(clientAddedSpy.count(), 1);
+    auto internalClient = clientAddedSpy.first().first().value<ShellClient*>();
+    QCOMPARE(internalClient->surface()->scale(), 2);
+
+    QMetaObject::invokeMethod(kwinApp()->platform(), "setVirtualOutputs", Qt::DirectConnection, Q_ARG(int, 2));
+}
+
+
 }
 
 WAYLANDTEST_MAIN(KWin::InternalWindowTest)
diff --git a/autotests/integration/kwin_wayland_test.h b/autotests/integration/kwin_wayland_test.h
index 4c7b183c3d..6d62e0a7c6 100644
--- a/autotests/integration/kwin_wayland_test.h
+++ b/autotests/integration/kwin_wayland_test.h
@@ -207,9 +207,9 @@ int main(int argc, char *argv[]) \
 }
 
 #ifdef NO_XWAYLAND
-#define WAYLANDTEST_MAIN(TestObject) WAYLANDTEST_MAIN_HELPER(TestObject, QCoreApplication::setAttribute(Qt::AA_DisableHighDpiScaling), KWin::Application::OperationModeWaylandOnly)
+#define WAYLANDTEST_MAIN(TestObject) WAYLANDTEST_MAIN_HELPER(TestObject, QCoreApplication::setAttribute(Qt::AA_UseHighDpiPixmaps), KWin::Application::OperationModeWaylandOnly)
 #else
-#define WAYLANDTEST_MAIN(TestObject) WAYLANDTEST_MAIN_HELPER(TestObject, QCoreApplication::setAttribute(Qt::AA_DisableHighDpiScaling), KWin::Application::OperationModeXwayland)
+#define WAYLANDTEST_MAIN(TestObject) WAYLANDTEST_MAIN_HELPER(TestObject, QCoreApplication::setAttribute(Qt::AA_UseHighDpiPixmaps), KWin::Application::OperationModeXwayland)
 #endif
 
 #endif
diff --git a/main_wayland.cpp b/main_wayland.cpp
index f2cd475179..cd8a98c9f9 100644
--- a/main_wayland.cpp
+++ b/main_wayland.cpp
@@ -553,7 +553,7 @@ int main(int argc, char * argv[])
     qunsetenv("QT_DEVICE_PIXEL_RATIO");
     qputenv("QT_IM_MODULE", "qtvirtualkeyboard");
     qputenv("QSG_RENDER_LOOP", "basic");
-    QCoreApplication::setAttribute(Qt::AA_DisableHighDpiScaling);
+    QCoreApplication::setAttribute(Qt::AA_UseHighDpiPixmaps);
     KWin::ApplicationWayland a(argc, argv);
     a.setupTranslator();
     // reset QT_QPA_PLATFORM to a sane value for any processes started from KWin
diff --git a/plugins/qpa/backingstore.cpp b/plugins/qpa/backingstore.cpp
index 2ffe084cb8..a2f4fd2ac4 100644
--- a/plugins/qpa/backingstore.cpp
+++ b/plugins/qpa/backingstore.cpp
@@ -47,6 +47,7 @@ BackingStore::BackingStore(QWindow *w, KWayland::Client::ShmPool *shm)
             }
             const QSize size = m_backBuffer.size();
             m_backBuffer = QImage(b->address(), size.width(), size.height(), QImage::Format_ARGB32_Premultiplied);
+            m_backBuffer.setDevicePixelRatio(scale());
         }
     );
 }
@@ -61,7 +62,7 @@ QPaintDevice *BackingStore::paintDevice()
 void BackingStore::resize(const QSize &size, const QRegion &staticContents)
 {
     Q_UNUSED(staticContents)
-    m_size = size;
+    m_size = size * scale();
     if (!m_buffer) {
         return;
     }
@@ -73,13 +74,15 @@ void BackingStore::flush(QWindow *window, const QRegion &region, const QPoint &o
 {
     Q_UNUSED(region)
     Q_UNUSED(offset)
-    auto s = static_cast<Window *>(window->handle())->surface();
+
+    auto w = static_cast<Window *>(window->handle());
+    auto s = w->surface();
     if (!s) {
         return;
     }
     s->attachBuffer(m_buffer);
     // TODO: proper damage region
-    s->damage(QRect(QPoint(0, 0), m_backBuffer.size()));
+    s->damage(QRect(QPoint(0, 0), m_backBuffer.size() / scale()));
     s->commit(KWayland::Client::Surface::CommitFlag::None);
     waylandServer()->internalClientConection()->flush();
     waylandServer()->dispatch();
@@ -108,6 +111,7 @@ void BackingStore::beginPaint(const QRegion&)
     auto b = m_buffer.toStrongRef();
     b->setUsed(true);
     m_backBuffer = QImage(b->address(), m_size.width(), m_size.height(), QImage::Format_ARGB32_Premultiplied);
+    m_backBuffer.setDevicePixelRatio(scale());
     if (oldBuffer) {
         b->copy(oldBuffer->address());
     } else {
@@ -115,5 +119,10 @@ void BackingStore::beginPaint(const QRegion&)
     }
 }
 
+int BackingStore::scale() const
+{
+    return static_cast<Window *>(window()->handle())->scale();
+}
+
 }
 }
diff --git a/plugins/qpa/backingstore.h b/plugins/qpa/backingstore.h
index 0e00de6357..53c25a7788 100644
--- a/plugins/qpa/backingstore.h
+++ b/plugins/qpa/backingstore.h
@@ -48,6 +48,7 @@ public:
     void beginPaint(const QRegion &) override;
 
 private:
+    int scale() const;
     KWayland::Client::ShmPool *m_shm;
     QWeakPointer<KWayland::Client::Buffer> m_buffer;
     QImage m_backBuffer;
diff --git a/plugins/qpa/window.cpp b/plugins/qpa/window.cpp
index 37ce0e7254..04deadbe8b 100644
--- a/plugins/qpa/window.cpp
+++ b/plugins/qpa/window.cpp
@@ -20,6 +20,7 @@ along with this program.  If not, see <http://www.gnu.org/licenses/>.
 #define WL_EGL_PLATFORM 1
 #include "integration.h"
 #include "window.h"
+#include "screens.h"
 #include "../../shell_client.h"
 #include "../../wayland_server.h"
 #include <logging.h>
@@ -44,7 +45,10 @@ Window::Window(QWindow *window, KWayland::Client::Surface *surface, KWayland::Cl
     , m_shellSurface(shellSurface)
     , m_windowId(++s_windowId)
     , m_integration(integration)
+    , m_scale(screens()->maxScale())
 {
+    m_surface->setScale(m_scale);
+
     QObject::connect(m_surface, &QObject::destroyed, window, [this] { m_surface = nullptr;});
     QObject::connect(m_shellSurface, &QObject::destroyed, window, [this] { m_shellSurface = nullptr;});
     waylandServer()->internalClientConection()->flush();
@@ -94,14 +98,17 @@ void Window::setGeometry(const QRect &rect)
     if (rect.height() != oldRect.height()) {
         emit window()->heightChanged(rect.height());
     }
+
+    const QSize nativeSize = rect.size() * m_scale;
+
     if (m_contentFBO) {
-        if (m_contentFBO->width() != geometry().width() || m_contentFBO->height() != geometry().height()) {
+        if (m_contentFBO->size() != nativeSize) {
             m_resized = true;
         }
     }
 #if HAVE_WAYLAND_EGL
     if (m_eglWaylandWindow) {
-        wl_egl_window_resize(m_eglWaylandWindow, geometry().width(), geometry().height(), 0, 0);
+        wl_egl_window_resize(m_eglWaylandWindow, nativeSize.width(), nativeSize.height(), 0, 0);
     }
 #endif
     QWindowSystemInterface::handleGeometryChange(window(), geometry());
@@ -124,7 +131,7 @@ void Window::unmap()
 void Window::createEglSurface(EGLDisplay dpy, EGLConfig config)
 {
 #if HAVE_WAYLAND_EGL
-    const QSize size = window()->size();
+    const QSize size = window()->size() * m_scale;
     m_eglWaylandWindow = wl_egl_window_create(*m_surface, size.width(), size.height());
     if (!m_eglWaylandWindow) {
         return;
@@ -158,7 +165,8 @@ void Window::createFBO()
     if (m_contentFBO && r.size().isEmpty()) {
         return;
     }
-    m_contentFBO.reset(new QOpenGLFramebufferObject(r.width(), r.height(), QOpenGLFramebufferObject::CombinedDepthStencil));
+    const QSize nativeSize = r.size() * m_scale;
+    m_contentFBO.reset(new QOpenGLFramebufferObject(nativeSize.width(), nativeSize.height(), QOpenGLFramebufferObject::CombinedDepthStencil));
     if (!m_contentFBO->isValid()) {
         qCWarning(KWIN_QPA) << "Content FBO is not valid";
     }
@@ -174,5 +182,15 @@ ShellClient *Window::shellClient()
     return m_shellClient;
 }
 
+int Window::scale() const
+{
+    return m_scale;
+}
+
+qreal Window::devicePixelRatio() const
+{
+    return m_scale;
+}
+
 }
 }
diff --git a/plugins/qpa/window.h b/plugins/qpa/window.h
index e8caedc6e0..bc334c359c 100644
--- a/plugins/qpa/window.h
+++ b/plugins/qpa/window.h
@@ -74,6 +74,9 @@ public:
     }
     void createEglSurface(EGLDisplay dpy, EGLConfig config);
 
+    int scale() const;
+    qreal devicePixelRatio() const override;
+
     void bindContentFBO();
     const QSharedPointer<QOpenGLFramebufferObject> &contentFBO() const {
         return m_contentFBO;
@@ -96,6 +99,7 @@ private:
 #endif
     quint32 m_windowId;
     const Integration *m_integration;
+    int m_scale = 1;
 };
 
 }
diff --git a/shell_client.cpp b/shell_client.cpp
index 4255d6394d..810aa2fc71 100644
--- a/shell_client.cpp
+++ b/shell_client.cpp
@@ -510,9 +510,7 @@ void ShellClient::setInternalFramebufferObject(const QSharedPointer<QOpenGLFrame
         return;
     }
 
-    //Kwin currently scales internal windows to 1, so this is currently always correct
-    //when that changes, this needs adjusting
-    m_clientSize = fbo->size();
+    m_clientSize = fbo->size() / surface()->scale();
     markAsMapped();
     doSetGeometry(QRect(geom.topLeft(), m_clientSize));
     Toplevel::setInternalFramebufferObject(fbo);