diff --git a/effects.cpp b/effects.cpp
index 2a987250e..67d9ab298 100644
--- a/effects.cpp
+++ b/effects.cpp
@@ -590,7 +590,7 @@ void EffectsHandlerImpl::slotTabRemoved(EffectWindow *w, EffectWindow* leaderOfF
     emit tabRemoved(w, leaderOfFormerGroup);
 }
 
-void EffectsHandlerImpl::slotWindowDamaged(Toplevel* t, const QRect& r)
+void EffectsHandlerImpl::slotWindowDamaged(Toplevel* t, const QRegion& r)
 {
     if (!t->effectWindow()) {
         // can happen during tear down of window
diff --git a/effects.h b/effects.h
index d7d54d779..9b4b249d5 100644
--- a/effects.h
+++ b/effects.h
@@ -289,7 +289,7 @@ protected Q_SLOTS:
     void slotGeometryShapeChanged(KWin::Toplevel *t, const QRect &old);
     void slotFrameGeometryChanged(Toplevel *toplevel, const QRect &oldGeometry);
     void slotPaddingChanged(KWin::Toplevel *t, const QRect &old);
-    void slotWindowDamaged(KWin::Toplevel *t, const QRect& r);
+    void slotWindowDamaged(KWin::Toplevel *t, const QRegion& r);
 
 protected:
     void connectNotify(const QMetaMethod &signal) override;
diff --git a/effects/thumbnailaside/thumbnailaside.cpp b/effects/thumbnailaside/thumbnailaside.cpp
index 9bbda907e..629bae82b 100644
--- a/effects/thumbnailaside/thumbnailaside.cpp
+++ b/effects/thumbnailaside/thumbnailaside.cpp
@@ -73,7 +73,7 @@ void ThumbnailAsideEffect::paintWindow(EffectWindow *w, int mask, QRegion region
     painted |= region;
 }
 
-void ThumbnailAsideEffect::slotWindowDamaged(EffectWindow* w, const QRect&)
+void ThumbnailAsideEffect::slotWindowDamaged(EffectWindow* w, const QRegion&)
 {
     foreach (const Data & d, windows) {
         if (d.window == w)
diff --git a/effects/thumbnailaside/thumbnailaside.h b/effects/thumbnailaside/thumbnailaside.h
index ef3f0045e..15dc70265 100644
--- a/effects/thumbnailaside/thumbnailaside.h
+++ b/effects/thumbnailaside/thumbnailaside.h
@@ -55,7 +55,7 @@ private Q_SLOTS:
     void toggleCurrentThumbnail();
     void slotWindowClosed(KWin::EffectWindow *w);
     void slotWindowFrameGeometryChanged(KWin::EffectWindow *w, const QRect &old);
-    void slotWindowDamaged(KWin::EffectWindow* w, const QRect& damage);
+    void slotWindowDamaged(KWin::EffectWindow* w, const QRegion& damage);
     bool isActive() const override;
     void repaintAll();
 private:
diff --git a/libkwineffects/kwineffects.h b/libkwineffects/kwineffects.h
index 61cf95107..19f039feb 100644
--- a/libkwineffects/kwineffects.h
+++ b/libkwineffects/kwineffects.h
@@ -175,7 +175,7 @@ X-KDE-Library=kwin4_effect_cooleffect
 
 #define KWIN_EFFECT_API_MAKE_VERSION( major, minor ) (( major ) << 8 | ( minor ))
 #define KWIN_EFFECT_API_VERSION_MAJOR 0
-#define KWIN_EFFECT_API_VERSION_MINOR 231
+#define KWIN_EFFECT_API_VERSION_MINOR 232
 #define KWIN_EFFECT_API_VERSION KWIN_EFFECT_API_MAKE_VERSION( \
         KWIN_EFFECT_API_VERSION_MAJOR, KWIN_EFFECT_API_VERSION_MINOR )
 
@@ -1561,7 +1561,7 @@ Q_SIGNALS:
      * @param r Always empty.
      * @since 4.7
      */
-    void windowDamaged(KWin::EffectWindow *w, const QRect &r);
+    void windowDamaged(KWin::EffectWindow *w, const QRegion &r);
     /**
      * Signal emitted when a tabbox is added.
      * An effect who wants to replace the tabbox with itself should use refTabBox.
diff --git a/screencast/screencastmanager.cpp b/screencast/screencastmanager.cpp
index b5a2d70cc..8b34ac970 100644
--- a/screencast/screencastmanager.cpp
+++ b/screencast/screencastmanager.cpp
@@ -90,7 +90,7 @@ private:
         m_toplevel->addRepaintFull();
     }
 
-    void includeDamage(Toplevel *toplevel, const QRect &damage) {
+    void includeDamage(Toplevel *toplevel, const QRegion &damage) {
         Q_ASSERT(m_toplevel == toplevel);
         m_damagedRegion |= damage;
     }
diff --git a/toplevel.cpp b/toplevel.cpp
index 26ee4fe93..234f6d4ff 100644
--- a/toplevel.cpp
+++ b/toplevel.cpp
@@ -45,7 +45,7 @@ Toplevel::Toplevel()
     , m_screen(0)
     , m_skipCloseAnimation(false)
 {
-    connect(this, SIGNAL(damaged(KWin::Toplevel*,QRect)), SIGNAL(needsRepaint()));
+    connect(this, &Toplevel::damaged, this, &Toplevel::needsRepaint);
     connect(screens(), SIGNAL(changed()), SLOT(checkScreen()));
     connect(screens(), SIGNAL(countChanged(int,int)), SLOT(checkScreen()));
     setupCheckScreenConnection();
@@ -327,10 +327,10 @@ void Toplevel::damageNotifyEvent()
 {
     m_isDamaged = true;
 
-    // Note: The rect is supposed to specify the damage extents,
+    // Note: The damage is supposed to specify the damage extents,
     //       but we don't know it at this point. No one who connects
     //       to this signal uses the rect however.
-    emit damaged(this, QRect());
+    emit damaged(this, {});
 }
 
 bool Toplevel::compositing() const
@@ -421,12 +421,12 @@ void Toplevel::addDamageFull()
     const int offsetX = bufferRect.x() - frameRect.x();
     const int offsetY = bufferRect.y() - frameRect.y();
 
-    const QRect damagedRect = QRect(0, 0, bufferRect.width(), bufferRect.height());
+    const QRect damagedRect(0, 0, bufferRect.width(), bufferRect.height());
 
     damage_region = damagedRect;
     repaints_region |= damagedRect.translated(offsetX, offsetY);
 
-    emit damaged(this, damagedRect);
+    emit damaged(this, damage_region);
 }
 
 void Toplevel::resetDamage()
@@ -748,9 +748,7 @@ void Toplevel::addDamage(const QRegion &damage)
 {
     m_isDamaged = true;
     damage_region += damage;
-    for (const QRect &r : damage) {
-        emit damaged(this, r);
-    }
+    emit damaged(this, damage);
 }
 
 QByteArray Toplevel::windowRole() const
diff --git a/toplevel.h b/toplevel.h
index d159a2af2..2cea2f41f 100644
--- a/toplevel.h
+++ b/toplevel.h
@@ -585,7 +585,7 @@ public:
 
 Q_SIGNALS:
     void opacityChanged(KWin::Toplevel* toplevel, qreal oldOpacity);
-    void damaged(KWin::Toplevel* toplevel, const QRect& damage);
+    void damaged(KWin::Toplevel* toplevel, const QRegion& damage);
     void inputTransformationChanged();
     /**
      * This signal is emitted when the Toplevel's frame geometry changes.