diff --git a/src/plugins/platforms/wayland/qwaylandbuffer.cpp b/src/plugins/platforms/wayland/qwaylandbuffer.cpp
index a0fcc532f5b..076a0d57d74 100644
--- a/src/plugins/platforms/wayland/qwaylandbuffer.cpp
+++ b/src/plugins/platforms/wayland/qwaylandbuffer.cpp
@@ -66,7 +66,7 @@ void QWaylandBuffer::init(wl_buffer *buf)
 
 void QWaylandBuffer::release(void *data, wl_buffer *)
 {
-    static_cast<QWaylandBuffer *>(data)->mBusy = false;
+    static_cast<QWaylandBuffer *>(data)->mBusy--;
 }
 
 const wl_buffer_listener QWaylandBuffer::listener = {
diff --git a/src/plugins/platforms/wayland/qwaylandbuffer_p.h b/src/plugins/platforms/wayland/qwaylandbuffer_p.h
index 9e8cba2e490..b3513d1515e 100644
--- a/src/plugins/platforms/wayland/qwaylandbuffer_p.h
+++ b/src/plugins/platforms/wayland/qwaylandbuffer_p.h
@@ -73,14 +73,14 @@ public:
     virtual QSize size() const = 0;
     virtual int scale() const { return 1; }
 
-    void setBusy() { mBusy = true; }
-    bool busy() const { return mBusy; }
+    void setBusy() { mBusy++; }
+    bool busy() const { return mBusy > 0; }
 
 protected:
     struct wl_buffer *mBuffer;
 
 private:
-    bool mBusy;
+    int mBusy;
 
     static void release(void *data, wl_buffer *);
     static const wl_buffer_listener listener;
diff --git a/src/plugins/platforms/wayland/qwaylandwindow.cpp b/src/plugins/platforms/wayland/qwaylandwindow.cpp
index cac92a7e114..cff380e8fa2 100644
--- a/src/plugins/platforms/wayland/qwaylandwindow.cpp
+++ b/src/plugins/platforms/wayland/qwaylandwindow.cpp
@@ -261,6 +261,8 @@ void QWaylandWindow::reset(bool sendDestroyEvent)
         wl_callback_destroy(mFrameCallback);
         mFrameCallback = nullptr;
     }
+
+    mMask = QRegion();
 }
 
 QWaylandWindow *QWaylandWindow::fromWlSurface(::wl_surface *surface)
@@ -790,22 +792,27 @@ QWaylandAbstractDecoration *QWaylandWindow::decoration() const
     return mWindowDecoration;
 }
 
-static QWindow *topLevelWindow(QWindow *window)
+static QWaylandWindow *closestShellSurfaceWindow(QWindow *window)
 {
-    while (QWindow *parent = window->parent())
-        window = parent;
-    return window;
+    while (window) {
+        auto w = static_cast<QWaylandWindow *>(window->handle());
+        if (w->shellSurface())
+            return w;
+        window = window->transientParent() ? window->transientParent() : window->parent();
+    }
+    return nullptr;
 }
 
 QWaylandWindow *QWaylandWindow::transientParent() const
 {
-    // Take the top level window here, since the transient parent may be a QWidgetWindow
-    // or some other window without a shell surface, which is then not able to get mouse
-    // events.
-    if (auto transientParent = window()->transientParent())
-        return static_cast<QWaylandWindow *>(topLevelWindow(transientParent)->handle());
-    else if (QGuiApplication::focusWindow() && (window()->type() == Qt::ToolTip || window()->type() == Qt::Popup))
-        return static_cast<QWaylandWindow *>(topLevelWindow(QGuiApplication::focusWindow())->handle());
+    // Take the closest window with a shell surface, since the transient parent may be a
+    // QWidgetWindow or some other window without a shell surface, which is then not able to
+    // get mouse events.
+    if (auto transientParent = closestShellSurfaceWindow(window()->transientParent()))
+        return transientParent;
+
+    if (QGuiApplication::focusWindow() && (window()->type() == Qt::ToolTip || window()->type() == Qt::Popup))
+        return closestShellSurfaceWindow(QGuiApplication::focusWindow());
 
     return nullptr;
 }
diff --git a/src/plugins/platforms/wayland/qwaylandwlshellsurface.cpp b/src/plugins/platforms/wayland/qwaylandwlshellsurface.cpp
index 77434e98b6c..92223f45ee6 100644
--- a/src/plugins/platforms/wayland/qwaylandwlshellsurface.cpp
+++ b/src/plugins/platforms/wayland/qwaylandwlshellsurface.cpp
@@ -185,6 +185,7 @@ void QWaylandWlShellSurface::updateTransientParent(QWindow *parent)
             || testShowWithoutActivating(m_window->window()))
         flags |= WL_SHELL_SURFACE_TRANSIENT_INACTIVE;
 
+    Q_ASSERT(parent_wayland_window->object());
     set_transient(parent_wayland_window->object(),
                   transientPos.x(),
                   transientPos.y(),
@@ -211,15 +212,16 @@ void QWaylandWlShellSurface::setPopup(QWaylandWindow *parent, QWaylandInputDevic
         transientPos.setY(transientPos.y() + parent_wayland_window->decoration()->margins().top());
     }
 
+    Q_ASSERT(parent_wayland_window->object());
     set_popup(device->wl_seat(), serial, parent_wayland_window->object(),
               transientPos.x(), transientPos.y(), 0);
 }
 
 void QWaylandWlShellSurface::setType(Qt::WindowType type, QWaylandWindow *transientParent)
 {
-    if (type == Qt::Popup && transientParent)
+    if (type == Qt::Popup && transientParent && transientParent->object())
         setPopup(transientParent, m_window->display()->lastInputDevice(), m_window->display()->lastInputSerial());
-    else if (transientParent)
+    else if (transientParent && transientParent->object())
         updateTransientParent(transientParent->window());
     else
         setTopLevel();
diff --git a/tests/auto/wayland/client/tst_client.cpp b/tests/auto/wayland/client/tst_client.cpp
index 8acddfbe740..1eee90f49db 100644
--- a/tests/auto/wayland/client/tst_client.cpp
+++ b/tests/auto/wayland/client/tst_client.cpp
@@ -143,6 +143,8 @@ private slots:
     void touchDrag();
     void mouseDrag();
     void dontCrashOnMultipleCommits();
+    void hiddenTransientParent();
+    void hiddenPopupParent();
 
 private:
     MockCompositor *compositor;
@@ -360,6 +362,48 @@ void tst_WaylandClient::dontCrashOnMultipleCommits()
     QTRY_VERIFY(!compositor->surface());
 }
 
+void tst_WaylandClient::hiddenTransientParent()
+{
+    QWindow parent;
+    QWindow transient;
+
+    transient.setTransientParent(&parent);
+
+    parent.show();
+    QTRY_VERIFY(compositor->surface());
+
+    parent.hide();
+    QTRY_VERIFY(!compositor->surface());
+
+    transient.show();
+    QTRY_VERIFY(compositor->surface());
+}
+
+void tst_WaylandClient::hiddenPopupParent()
+{
+    TestWindow toplevel;
+    toplevel.show();
+
+    // wl_shell relies on a mouse event in order to send a serial and seat
+    // with the set_popup request.
+    QSharedPointer<MockSurface> surface;
+    QTRY_VERIFY(surface = compositor->surface());
+    QPoint mousePressPos(16, 16);
+    QCOMPARE(toplevel.mousePressEventCount, 0);
+    compositor->sendMousePress(surface, mousePressPos);
+    QTRY_COMPARE(toplevel.mousePressEventCount, 1);
+
+    QWindow popup;
+    popup.setTransientParent(&toplevel);
+    popup.setFlag(Qt::Popup, true);
+
+    toplevel.hide();
+    QTRY_VERIFY(!compositor->surface());
+
+    popup.show();
+    QTRY_VERIFY(compositor->surface());
+}
+
 int main(int argc, char **argv)
 {
     setenv("XDG_RUNTIME_DIR", ".", 1);