diff --git a/platform.h b/platform.h
--- a/platform.h
+++ b/platform.h
@@ -65,17 +65,6 @@
 class DecoratedClientImpl;
 }
 
-class KWIN_EXPORT Outputs : public QVector<AbstractOutput*>
-{
-public:
-    Outputs(){};
-    template <typename T>
-    Outputs(const QVector<T> &other) {
-        resize(other.size());
-        std::copy(other.constBegin(), other.constEnd(), begin());
-    }
-};
-
 class KWIN_EXPORT Platform : public QObject
 {
     Q_OBJECT
@@ -419,13 +408,9 @@
     }
 
     // outputs with connections (org_kde_kwin_outputdevice)
-    virtual Outputs outputs() const {
-        return Outputs();
-    }
+    virtual QVector<AbstractOutput *> outputs() const;
     // actively compositing outputs (wl_output)
-    virtual Outputs enabledOutputs() const {
-        return Outputs();
-    }
+    virtual QVector<AbstractOutput *> enabledOutputs() const;
     AbstractOutput *findOutput(const QByteArray &uuid);
 
     /**
diff --git a/platform.cpp b/platform.cpp
--- a/platform.cpp
+++ b/platform.cpp
@@ -547,6 +547,16 @@
     new EffectsHandlerImpl(compositor, scene);
 }
 
+QVector<AbstractOutput *> Platform::outputs() const
+{
+    return QVector<AbstractOutput *>();
+}
+
+QVector<AbstractOutput *> Platform::enabledOutputs() const
+{
+    return QVector<AbstractOutput *>();
+}
+
 QString Platform::supportInformation() const
 {
     return QStringLiteral("Name: %1\n").arg(metaObject()->className());
diff --git a/plugins/platforms/drm/drm_backend.h b/plugins/platforms/drm/drm_backend.h
--- a/plugins/platforms/drm/drm_backend.h
+++ b/plugins/platforms/drm/drm_backend.h
@@ -80,8 +80,8 @@
     int fd() const {
         return m_fd;
     }
-    Outputs outputs() const override;
-    Outputs enabledOutputs() const override;
+    QVector<AbstractOutput *> outputs() const override;
+    QVector<AbstractOutput *> enabledOutputs() const override;
     QVector<DrmOutput*> drmOutputs() const {
         return m_outputs;
     }
diff --git a/plugins/platforms/drm/drm_backend.cpp b/plugins/platforms/drm/drm_backend.cpp
--- a/plugins/platforms/drm/drm_backend.cpp
+++ b/plugins/platforms/drm/drm_backend.cpp
@@ -132,14 +132,14 @@
     Platform::prepareShutdown();
 }
 
-Outputs DrmBackend::outputs() const
+QVector<AbstractOutput *> DrmBackend::outputs() const
 {
-    return m_outputs;
+    return qvector_cast<AbstractOutput *>(m_outputs);
 }
 
-Outputs DrmBackend::enabledOutputs() const
+QVector<AbstractOutput *> DrmBackend::enabledOutputs() const
 {
-    return m_enabledOutputs;
+    return qvector_cast<AbstractOutput *>(m_enabledOutputs);
 }
 
 void DrmBackend::createDpmsFilter()
diff --git a/plugins/platforms/fbdev/fb_backend.h b/plugins/platforms/fbdev/fb_backend.h
--- a/plugins/platforms/fbdev/fb_backend.h
+++ b/plugins/platforms/fbdev/fb_backend.h
@@ -82,8 +82,8 @@
         return m_bgr;
     }
 
-    Outputs outputs() const override;
-    Outputs enabledOutputs() const override;
+    QVector<AbstractOutput *> outputs() const override;
+    QVector<AbstractOutput *> enabledOutputs() const override;
 
     QVector<CompositingType> supportedCompositors() const override {
         return QVector<CompositingType>{QPainterCompositing};
diff --git a/plugins/platforms/fbdev/fb_backend.cpp b/plugins/platforms/fbdev/fb_backend.cpp
--- a/plugins/platforms/fbdev/fb_backend.cpp
+++ b/plugins/platforms/fbdev/fb_backend.cpp
@@ -266,14 +266,14 @@
     }
 }
 
-Outputs FramebufferBackend::outputs() const
+QVector<AbstractOutput *> FramebufferBackend::outputs() const
 {
-    return m_outputs;
+    return qvector_cast<AbstractOutput *>(m_outputs);
 }
 
-Outputs FramebufferBackend::enabledOutputs() const
+QVector<AbstractOutput *> FramebufferBackend::enabledOutputs() const
 {
-    return m_outputs;
+    return qvector_cast<AbstractOutput *>(m_outputs);
 }
 
 }
diff --git a/plugins/platforms/hwcomposer/hwcomposer_backend.h b/plugins/platforms/hwcomposer/hwcomposer_backend.h
--- a/plugins/platforms/hwcomposer/hwcomposer_backend.h
+++ b/plugins/platforms/hwcomposer/hwcomposer_backend.h
@@ -77,8 +77,8 @@
     Screens *createScreens(QObject *parent = nullptr) override;
     OpenGLBackend *createOpenGLBackend() override;
 
-    Outputs outputs() const override;
-    Outputs enabledOutputs() const override;
+    QVector<AbstractOutput *> outputs() const override;
+    QVector<AbstractOutput *> enabledOutputs() const override;
 
     QSize size() const;
     QSize screenSize() const override;
diff --git a/plugins/platforms/hwcomposer/hwcomposer_backend.cpp b/plugins/platforms/hwcomposer/hwcomposer_backend.cpp
--- a/plugins/platforms/hwcomposer/hwcomposer_backend.cpp
+++ b/plugins/platforms/hwcomposer/hwcomposer_backend.cpp
@@ -356,15 +356,15 @@
     return new HwcomposerScreens(this, parent);
 }
 
-Outputs HwcomposerBackend::outputs() const
+QVector<AbstractOutput *> HwcomposerBackend::outputs() const
 {
     if (!m_output.isNull()) {
-        return QVector<HwcomposerOutput*>({m_output.data()});
+        return { m_output.data() };
     }
     return {};
 }
 
-Outputs HwcomposerBackend::enabledOutputs() const
+QVector<AbstractOutput *> HwcomposerBackend::enabledOutputs() const
 {
     return outputs();
 }
diff --git a/plugins/platforms/virtual/virtual_backend.h b/plugins/platforms/virtual/virtual_backend.h
--- a/plugins/platforms/virtual/virtual_backend.h
+++ b/plugins/platforms/virtual/virtual_backend.h
@@ -30,7 +30,6 @@
 
 namespace KWin
 {
-class VirtualOutput;
 
 class KWIN_EXPORT VirtualBackend : public Platform
 {
@@ -54,8 +53,8 @@
 
     Q_INVOKABLE void setVirtualOutputs(int count, QVector<QRect> geometries = QVector<QRect>(), QVector<int> scales = QVector<int>());
 
-    Outputs outputs() const override;
-    Outputs enabledOutputs() const override;
+    QVector<AbstractOutput *> outputs() const override;
+    QVector<AbstractOutput *> enabledOutputs() const override;
 
     QVector<CompositingType> supportedCompositors() const override {
         if (selectedCompositor() != NoCompositing) {
@@ -68,8 +67,8 @@
     void virtualOutputsSet(bool countChanged);
 
 private:
-    QVector<VirtualOutput*> m_outputs;
-    QVector<VirtualOutput*> m_enabledOutputs;
+    QVector<AbstractOutput *> m_outputs;
+    QVector<AbstractOutput *> m_enabledOutputs;
 
     QScopedPointer<QTemporaryDir> m_screenshotDir;
 };
diff --git a/plugins/platforms/virtual/virtual_backend.cpp b/plugins/platforms/virtual/virtual_backend.cpp
--- a/plugins/platforms/virtual/virtual_backend.cpp
+++ b/plugins/platforms/virtual/virtual_backend.cpp
@@ -102,12 +102,12 @@
     return new EglGbmBackend(this);
 }
 
-Outputs VirtualBackend::outputs() const
+QVector<AbstractOutput *> VirtualBackend::outputs() const
 {
     return m_outputs;
 }
 
-Outputs VirtualBackend::enabledOutputs() const
+QVector<AbstractOutput *> VirtualBackend::enabledOutputs() const
 {
     return m_enabledOutputs;
 }
diff --git a/plugins/platforms/wayland/wayland_backend.h b/plugins/platforms/wayland/wayland_backend.h
--- a/plugins/platforms/wayland/wayland_backend.h
+++ b/plugins/platforms/wayland/wayland_backend.h
@@ -208,8 +208,8 @@
     void checkBufferSwap();
 
     WaylandOutput* getOutputAt(const QPointF globalPosition);
-    Outputs outputs() const override;
-    Outputs enabledOutputs() const override;
+    QVector<AbstractOutput *> outputs() const override;
+    QVector<AbstractOutput *> enabledOutputs() const override;
     QVector<WaylandOutput*> waylandOutputs() const {
         return m_outputs;
     }
diff --git a/plugins/platforms/wayland/wayland_backend.cpp b/plugins/platforms/wayland/wayland_backend.cpp
--- a/plugins/platforms/wayland/wayland_backend.cpp
+++ b/plugins/platforms/wayland/wayland_backend.cpp
@@ -835,15 +835,15 @@
 #endif
 }
 
-Outputs WaylandBackend::outputs() const
+QVector<AbstractOutput *> WaylandBackend::outputs() const
 {
-    return m_outputs;
+    return qvector_cast<AbstractOutput *>(m_outputs);
 }
 
-Outputs WaylandBackend::enabledOutputs() const
+QVector<AbstractOutput *> WaylandBackend::enabledOutputs() const
 {
     // all outputs are enabled
-    return m_outputs;
+    return qvector_cast<AbstractOutput *>(m_outputs);
 }
 
 }
diff --git a/plugins/platforms/x11/standalone/x11_platform.h b/plugins/platforms/x11/standalone/x11_platform.h
--- a/plugins/platforms/x11/standalone/x11_platform.h
+++ b/plugins/platforms/x11/standalone/x11_platform.h
@@ -75,8 +75,8 @@
     void initOutputs();
     void updateOutputs();
 
-    Outputs outputs() const override;
-    Outputs enabledOutputs() const override;
+    QVector<AbstractOutput *> outputs() const override;
+    QVector<AbstractOutput *> enabledOutputs() const override;
 
 protected:
     void doHideCursor() override;
diff --git a/plugins/platforms/x11/standalone/x11_platform.cpp b/plugins/platforms/x11/standalone/x11_platform.cpp
--- a/plugins/platforms/x11/standalone/x11_platform.cpp
+++ b/plugins/platforms/x11/standalone/x11_platform.cpp
@@ -548,14 +548,14 @@
     }
 }
 
-Outputs X11StandalonePlatform::outputs() const
+QVector<AbstractOutput *> X11StandalonePlatform::outputs() const
 {
-    return m_outputs;
+    return qvector_cast<AbstractOutput *>(m_outputs);
 }
 
-Outputs X11StandalonePlatform::enabledOutputs() const
+QVector<AbstractOutput *> X11StandalonePlatform::enabledOutputs() const
 {
-    return m_outputs;
+    return qvector_cast<AbstractOutput *>(m_outputs);
 }
 
 }
diff --git a/plugins/platforms/x11/windowed/x11windowed_backend.h b/plugins/platforms/x11/windowed/x11windowed_backend.h
--- a/plugins/platforms/x11/windowed/x11windowed_backend.h
+++ b/plugins/platforms/x11/windowed/x11windowed_backend.h
@@ -81,8 +81,8 @@
         return QVector<CompositingType>{OpenGLCompositing, QPainterCompositing};
     }
 
-    Outputs outputs() const override;
-    Outputs enabledOutputs() const override;
+    QVector<AbstractOutput *> outputs() const override;
+    QVector<AbstractOutput *> enabledOutputs() const override;
 
 Q_SIGNALS:
     void sizeChanged();
diff --git a/plugins/platforms/x11/windowed/x11windowed_backend.cpp b/plugins/platforms/x11/windowed/x11windowed_backend.cpp
--- a/plugins/platforms/x11/windowed/x11windowed_backend.cpp
+++ b/plugins/platforms/x11/windowed/x11windowed_backend.cpp
@@ -534,14 +534,14 @@
     return m_outputs.at(screen)->window();
 }
 
-Outputs X11WindowedBackend::outputs() const
+QVector<AbstractOutput *> X11WindowedBackend::outputs() const
 {
-    return m_outputs;
+    return qvector_cast<AbstractOutput *>(m_outputs);
 }
 
-Outputs X11WindowedBackend::enabledOutputs() const
+QVector<AbstractOutput *> X11WindowedBackend::enabledOutputs() const
 {
-    return m_outputs;
+    return qvector_cast<AbstractOutput *>(m_outputs);
 }
 
 }
diff --git a/utils.h b/utils.h
--- a/utils.h
+++ b/utils.h
@@ -233,6 +233,15 @@
     void setupChildProcess() override;
 };
 
+template <typename To, typename From>
+QVector<To> qvector_cast(const QVector<From> &collection)
+{
+    QVector<To> mapped;
+    mapped.reserve(collection.size());
+    std::copy(collection.constBegin(), collection.constEnd(), std::back_inserter(mapped));
+    return mapped;
+}
+
 } // namespace
 
 // Must be outside namespace