diff --git a/abstract_client.cpp b/abstract_client.cpp
index f3fcb50d7c..8969d291a1 100644
--- a/abstract_client.cpp
+++ b/abstract_client.cpp
@@ -2575,6 +2575,16 @@ QRect AbstractClient::inputGeometry() const
     return Toplevel::inputGeometry();
 }
 
+bool AbstractClient::hitTest(const QPoint &point) const
+{
+    if (isDecorated()) {
+        if (m_decoration.inputRegion.contains(mapToFrame(point))) {
+            return true;
+        }
+    }
+    return Toplevel::hitTest(point);
+}
+
 QRect AbstractClient::virtualKeyboardGeometry() const
 {
     return m_virtualKeyboardGeometry;
diff --git a/abstract_client.h b/abstract_client.h
index 79ab9ba0c4..9aecb96110 100644
--- a/abstract_client.h
+++ b/abstract_client.h
@@ -754,6 +754,7 @@ public:
     virtual void showContextHelp();
 
     QRect inputGeometry() const override;
+    bool hitTest(const QPoint &point) const override;
 
     /**
      * @returns the geometry of the virtual keyboard
diff --git a/autotests/integration/pointer_input.cpp b/autotests/integration/pointer_input.cpp
index 63f27ade3f..89b0451f8d 100644
--- a/autotests/integration/pointer_input.cpp
+++ b/autotests/integration/pointer_input.cpp
@@ -25,6 +25,7 @@
 #include <KWayland/Client/connection_thread.h>
 #include <KWayland/Client/compositor.h>
 #include <KWayland/Client/pointer.h>
+#include <KWayland/Client/region.h>
 #include <KWayland/Client/seat.h>
 #include <KWayland/Client/server_decoration.h>
 #include <KWayland/Client/shm_pool.h>
@@ -123,6 +124,8 @@ private Q_SLOTS:
     void testResizeCursor();
     void testMoveCursor();
     void testHideShowCursor();
+    void testDefaultInputRegion();
+    void testEmptyInputRegion();
 
 private:
     void render(KWayland::Client::Surface *surface, const QSize &size = QSize(100, 50));
@@ -1619,6 +1622,52 @@ void PointerInputTest::testHideShowCursor()
     QCOMPARE(kwinApp()->platform()->isCursorHidden(), false);
 }
 
+void PointerInputTest::testDefaultInputRegion()
+{
+    // This test verifies that a surface that hasn't specified the input region can be focused.
+
+    // Create a test client.
+    using namespace KWayland::Client;
+    QScopedPointer<Surface> surface(Test::createSurface());
+    QVERIFY(!surface.isNull());
+    QScopedPointer<XdgShellSurface> shellSurface(Test::createXdgShellStableSurface(surface.data()));
+    QVERIFY(!shellSurface.isNull());
+    AbstractClient *client = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
+    QVERIFY(client);
+
+    // Move the point to the center of the surface.
+    Cursors::self()->mouse()->setPos(client->frameGeometry().center());
+    QCOMPARE(waylandServer()->seat()->focusedPointerSurface(), client->surface());
+
+    // Destroy the test client.
+    shellSurface.reset();
+    QVERIFY(Test::waitForWindowDestroyed(client));
+}
+
+void PointerInputTest::testEmptyInputRegion()
+{
+    // This test verifies that a surface that has specified an empty input region can't be focused.
+
+    // Create a test client.
+    using namespace KWayland::Client;
+    QScopedPointer<Surface> surface(Test::createSurface());
+    QVERIFY(!surface.isNull());
+    std::unique_ptr<KWayland::Client::Region> inputRegion(m_compositor->createRegion(QRegion()));
+    surface->setInputRegion(inputRegion.get());
+    QScopedPointer<XdgShellSurface> shellSurface(Test::createXdgShellStableSurface(surface.data()));
+    QVERIFY(!shellSurface.isNull());
+    AbstractClient *client = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
+    QVERIFY(client);
+
+    // Move the point to the center of the surface.
+    Cursors::self()->mouse()->setPos(client->frameGeometry().center());
+    QVERIFY(!waylandServer()->seat()->focusedPointerSurface());
+
+    // Destroy the test client.
+    shellSurface.reset();
+    QVERIFY(Test::waitForWindowDestroyed(client));
+}
+
 }
 
 WAYLANDTEST_MAIN(KWin::PointerInputTest)
diff --git a/input.cpp b/input.cpp
index 0fbc2871d6..6f44cd7d12 100644
--- a/input.cpp
+++ b/input.cpp
@@ -2418,17 +2418,6 @@ Qt::MouseButtons InputRedirection::qtButtonStates() const
     return m_pointer->buttons();
 }
 
-static bool acceptsInput(Toplevel *t, const QPoint &pos)
-{
-    const QRegion input = t->inputShape();
-    if (input.isEmpty()) {
-        return true;
-    }
-    // TODO: What about sub-surfaces sticking outside the main surface?
-    const QPoint localPoint = pos - t->bufferGeometry().topLeft();
-    return input.contains(localPoint);
-}
-
 Toplevel *InputRedirection::findToplevel(const QPoint &pos)
 {
     if (!Workspace::self()) {
@@ -2443,7 +2432,7 @@ Toplevel *InputRedirection::findToplevel(const QPoint &pos)
         }
         const QList<Unmanaged *> &unmanaged = Workspace::self()->unmanagedList();
         foreach (Unmanaged *u, unmanaged) {
-            if (u->inputGeometry().contains(pos) && acceptsInput(u, pos)) {
+            if (u->hitTest(pos)) {
                 return u;
             }
         }
@@ -2482,7 +2471,7 @@ Toplevel *InputRedirection::findManagedToplevel(const QPoint &pos)
                 continue;
             }
         }
-        if (t->inputGeometry().contains(pos) && acceptsInput(t, pos)) {
+        if (t->hitTest(pos)) {
             return t;
         }
     } while (it != stacking.begin());
diff --git a/inputpanelv1client.cpp b/inputpanelv1client.cpp
index 4d56d94866..50bbbe86c3 100644
--- a/inputpanelv1client.cpp
+++ b/inputpanelv1client.cpp
@@ -107,9 +107,6 @@ NET::WindowType InputPanelV1Client::windowType(bool, int) const
 
 QRect InputPanelV1Client::inputGeometry() const
 {
-    if (surface()->inputIsInfinite()) {
-        return frameGeometry();
-    }
     return surface()->input().boundingRect().translated(pos());
 }
 
diff --git a/pointer_input.cpp b/pointer_input.cpp
index 4812a11d37..6966e8923a 100644
--- a/pointer_input.cpp
+++ b/pointer_input.cpp
@@ -620,8 +620,7 @@ template <typename T>
 static QRegion getConstraintRegion(Toplevel *t, T *constraint)
 {
     const QRegion windowShape = t->inputShape();
-    const QRegion windowRegion = windowShape.isEmpty() ? QRegion(0, 0, t->clientSize().width(), t->clientSize().height()) : windowShape;
-    const QRegion intersected = constraint->region().isEmpty() ? windowRegion : windowRegion.intersected(constraint->region());
+    const QRegion intersected = constraint->region().isEmpty() ? windowShape : windowShape.intersected(constraint->region());
     return intersected.translated(t->pos() + t->clientPos());
 }
 
diff --git a/toplevel.cpp b/toplevel.cpp
index 0694361185..126c8165ed 100644
--- a/toplevel.cpp
+++ b/toplevel.cpp
@@ -789,6 +789,14 @@ QMatrix4x4 Toplevel::inputTransformation() const
     return m;
 }
 
+bool Toplevel::hitTest(const QPoint &point) const
+{
+    if (m_surface && m_surface->isMapped()) {
+        return m_surface->inputSurfaceAt(mapToLocal(point));
+    }
+    return inputGeometry().contains(point);
+}
+
 QPoint Toplevel::mapToFrame(const QPoint &point) const
 {
     return point - frameGeometry().topLeft();
diff --git a/toplevel.h b/toplevel.h
index e16cd2176b..a7674928e0 100644
--- a/toplevel.h
+++ b/toplevel.h
@@ -540,6 +540,11 @@ public:
      */
     virtual QMatrix4x4 inputTransformation() const;
 
+    /**
+     * Returns @c true if the toplevel can accept input at the specified position @a point.
+     */
+    virtual bool hitTest(const QPoint &point) const;
+
     /**
      * The window has a popup grab. This means that when it got mapped the
      * parent window had an implicit (pointer) grab.