diff --git a/autotests/integration/decoration_input_test.cpp b/autotests/integration/decoration_input_test.cpp
--- a/autotests/integration/decoration_input_test.cpp
+++ b/autotests/integration/decoration_input_test.cpp
@@ -92,8 +92,6 @@
 #define COMPARE(actual, expected) \
     if (!QTest::qCompare(actual, expected, #actual, #expected, __FILE__, __LINE__))\
         return nullptr;
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    VERIFY(clientAddedSpy.isValid());
 
     Surface *surface = Test::createSurface(Test::waylandCompositor());
     VERIFY(surface);
@@ -107,13 +105,9 @@
     VERIFY(decoSpy.wait());
     COMPARE(deco->mode(), ServerSideDecoration::Mode::Server);
     // let's render
-    Test::render(surface, QSize(500, 50), Qt::blue);
-
-    Test::flushWaylandConnection();
-    VERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
+    auto c = Test::renderAndWaitForShown(surface, QSize(500, 50), Qt::blue);
     VERIFY(c);
-    COMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    COMPARE(workspace()->activeClient(), c);
 
 #undef VERIFY
 #undef COMPARE
diff --git a/autotests/integration/dont_crash_cancel_animation.cpp b/autotests/integration/dont_crash_cancel_animation.cpp
--- a/autotests/integration/dont_crash_cancel_animation.cpp
+++ b/autotests/integration/dont_crash_cancel_animation.cpp
@@ -52,10 +52,6 @@
     void init();
     void cleanup();
     void testScript();
-
-private:
-    void unlock();
-    AbstractClient *showWindow();
 };
 
 void DontCrashCancelAnimationFromAnimationEndedTest::initTestCase()
@@ -101,21 +97,14 @@
 
     using namespace KWayland::Client;
     // create a window
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     Surface *surface = Test::createSurface(Test::waylandCompositor());
     QVERIFY(surface);
     ShellSurface *shellSurface = Test::createShellSurface(surface, surface);
     QVERIFY(shellSurface);
     // let's render
-    Test::render(surface, QSize(100, 50), Qt::blue);
-
-    Test::flushWaylandConnection();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
+    auto c = Test::renderAndWaitForShown(surface, QSize(100, 50), Qt::blue);
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
 
     // make sure we animate
     QTest::qWait(200);
diff --git a/autotests/integration/dont_crash_no_border.cpp b/autotests/integration/dont_crash_no_border.cpp
--- a/autotests/integration/dont_crash_no_border.cpp
+++ b/autotests/integration/dont_crash_no_border.cpp
@@ -98,8 +98,6 @@
 {
     // create a window and ensure that this doesn't crash
         using namespace KWayland::Client;
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
 
     QScopedPointer<Surface> surface(Test::createSurface());
     QVERIFY(!surface.isNull());
@@ -113,13 +111,9 @@
     QVERIFY(decoSpy.wait());
     QCOMPARE(deco->mode(), ServerSideDecoration::Mode::Server);
     // let's render
-    Test::render(surface.data(), QSize(500, 50), Qt::blue);
-
-    Test::flushWaylandConnection();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(500, 50), Qt::blue);
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
     QVERIFY(!c->isDecorated());
 }
 
diff --git a/autotests/integration/kwin_wayland_test.h b/autotests/integration/kwin_wayland_test.h
--- a/autotests/integration/kwin_wayland_test.h
+++ b/autotests/integration/kwin_wayland_test.h
@@ -45,6 +45,8 @@
 namespace KWin
 {
 
+class ShellClient;
+
 class WaylandTestApplication : public Application
 {
     Q_OBJECT
@@ -116,6 +118,17 @@
  * The @p surface gets damaged and committed, thus it's rendered.
  **/
 void render(KWayland::Client::Surface *surface, const QSize &size, const QColor &color, const QImage::Format &format = QImage::Format_ARGB32);
+
+/**
+ * Waits till a new ShellClient is shown and returns the created ShellClient.
+ * If no ShellClient gets shown during @p timeout @c null is returned.
+ **/
+ShellClient *waitForWaylandWindowShown(int timeout = 5000);
+
+/**
+ * Combination of @link{render} and @link{waitForWaylandWindowShown}.
+ **/
+ShellClient *renderAndWaitForShown(KWayland::Client::Surface *surface, const QSize &size, const QColor &color, const QImage::Format &format = QImage::Format_ARGB32, int timeout = 5000);
 }
 
 }
diff --git a/autotests/integration/lockscreen.cpp b/autotests/integration/lockscreen.cpp
--- a/autotests/integration/lockscreen.cpp
+++ b/autotests/integration/lockscreen.cpp
@@ -161,21 +161,16 @@
 #define COMPARE(actual, expected) \
     if (!QTest::qCompare(actual, expected, #actual, #expected, __FILE__, __LINE__))\
         return nullptr;
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    VERIFY(clientAddedSpy.isValid());
 
     Surface *surface = Test::createSurface(m_compositor);
     VERIFY(surface);
     ShellSurface *shellSurface = Test::createShellSurface(surface, surface);
     VERIFY(shellSurface);
     // let's render
-    Test::render(surface, QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface, QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    VERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     VERIFY(c);
-    COMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    COMPARE(workspace()->activeClient(), c);
 
 #undef VERIFY
 #undef COMPARE
diff --git a/autotests/integration/maximize_test.cpp b/autotests/integration/maximize_test.cpp
--- a/autotests/integration/maximize_test.cpp
+++ b/autotests/integration/maximize_test.cpp
@@ -87,20 +87,15 @@
 void TestMaximized::testMaximizedPassedToDeco()
 {
     // this test verifies that when a ShellClient gets maximized the Decoration receives the signal
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
     QScopedPointer<Surface> surface(Test::createSurface());
     QScopedPointer<ShellSurface> shellSurface(Test::createShellSurface(surface.data()));
     QScopedPointer<ServerSideDecoration> ssd(Test::waylandServerSideDecoration()->create(surface.data()));
 
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto client = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
     QSignalSpy sizeChangedSpy(shellSurface.data(), &ShellSurface::sizeChanged);
     QVERIFY(sizeChangedSpy.isValid());
 
-    QVERIFY(clientAddedSpy.isEmpty());
-    QVERIFY(clientAddedSpy.wait());
-    auto client = clientAddedSpy.first().first().value<ShellClient*>();
     QVERIFY(client);
     QVERIFY(client->isDecorated());
     auto decoration = client->decoration();
@@ -147,9 +142,6 @@
 void TestMaximized::testInitiallyMaximized()
 {
     // this test verifies that a window created as maximized, will be maximized
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     QScopedPointer<Surface> surface(Test::createSurface());
     QScopedPointer<ShellSurface> shellSurface(Test::createShellSurface(surface.data()));
 
@@ -161,11 +153,7 @@
     QCOMPARE(shellSurface->size(), QSize(1280, 1024));
 
     // now let's render in an incorrect size
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
-
-    QVERIFY(clientAddedSpy.isEmpty());
-    QVERIFY(clientAddedSpy.wait());
-    auto client = clientAddedSpy.first().first().value<ShellClient*>();
+    auto client = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
     QVERIFY(client);
     QCOMPARE(client->geometry(), QRect(0, 0, 100, 50));
     QEXPECT_FAIL("", "Should go out of maximzied", Continue);
diff --git a/autotests/integration/move_resize_window_test.cpp b/autotests/integration/move_resize_window_test.cpp
--- a/autotests/integration/move_resize_window_test.cpp
+++ b/autotests/integration/move_resize_window_test.cpp
@@ -105,24 +105,18 @@
 {
     using namespace KWayland::Client;
 
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     QScopedPointer<Surface> surface(Test::createSurface());
     QVERIFY(!surface.isNull());
 
     QScopedPointer<ShellSurface> shellSurface(Test::createShellSurface(surface.data()));
     QVERIFY(!shellSurface.isNull());
     QSignalSpy sizeChangeSpy(shellSurface.data(), &ShellSurface::sizeChanged);
     QVERIFY(sizeChangeSpy.isValid());
     // let's render
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
     QCOMPARE(c->geometry(), QRect(0, 0, 100, 50));
     QSignalSpy geometryChangedSpy(c, &AbstractClient::geometryChanged);
     QVERIFY(geometryChangedSpy.isValid());
@@ -203,24 +197,18 @@
 {
     using namespace KWayland::Client;
 
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     QScopedPointer<Surface> surface(Test::createSurface());
     QVERIFY(!surface.isNull());
 
     QScopedPointer<ShellSurface> shellSurface(Test::createShellSurface(surface.data()));
     QVERIFY(!shellSurface.isNull());
     QSignalSpy sizeChangeSpy(shellSurface.data(), &ShellSurface::sizeChanged);
     QVERIFY(sizeChangeSpy.isValid());
     // let's render
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
     QCOMPARE(c->geometry(), QRect(0, 0, 100, 50));
 
     // let's place it centered
@@ -247,9 +235,6 @@
 {
     using namespace KWayland::Client;
 
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     QScopedPointer<Surface> surface1(Test::createSurface());
     QVERIFY(!surface1.isNull());
     QScopedPointer<Surface> surface2(Test::createSurface());
@@ -267,17 +252,13 @@
     QVERIFY(!shellSurface3.isNull());
     QScopedPointer<ShellSurface> shellSurface4(Test::createShellSurface(surface4.data()));
     QVERIFY(!shellSurface4.isNull());
-    auto renderWindow = [this, &clientAddedSpy] (Surface *surface, const QString &methodCall, const QRect &expectedGeometry) {
+    auto renderWindow = [this] (Surface *surface, const QString &methodCall, const QRect &expectedGeometry) {
         // let's render
-        Test::render(surface, QSize(10, 10), Qt::blue);
+        auto c = Test::renderAndWaitForShown(surface, QSize(10, 10), Qt::blue);
 
-        m_connection->flush();
-        QVERIFY(clientAddedSpy.wait());
-        AbstractClient *c = workspace()->activeClient();
         QVERIFY(c);
-        QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+        QCOMPARE(workspace()->activeClient(), c);
         QCOMPARE(c->geometry().size(), QSize(10, 10));
-        clientAddedSpy.clear();
         // let's place it centered
         Placement::self()->placeCentered(c, QRect(0, 0, 1280, 1024));
         QCOMPARE(c->geometry(), QRect(635, 507, 10, 10));
@@ -293,13 +274,10 @@
     QVERIFY(!surface.isNull());
     QScopedPointer<ShellSurface> shellSurface(Test::createShellSurface(surface.data()));
     QVERIFY(!shellSurface.isNull());
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
     // let's place it centered
     Placement::self()->placeCentered(c, QRect(0, 0, 1280, 1024));
     QCOMPARE(c->geometry(), QRect(590, 487, 100, 50));
@@ -323,18 +301,14 @@
 void MoveResizeWindowTest::testGrowShrink()
 {
     using namespace KWayland::Client;
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
 
     // block geometry helper
     QScopedPointer<Surface> surface1(Test::createSurface());
     QVERIFY(!surface1.isNull());
     QScopedPointer<ShellSurface> shellSurface1(Test::createShellSurface(surface1.data()));
     QVERIFY(!shellSurface1.isNull());
     Test::render(surface1.data(), QSize(650, 514), Qt::blue);
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    clientAddedSpy.clear();
+    QVERIFY(Test::waitForWaylandWindowShown());
     workspace()->slotWindowPackRight();
     workspace()->slotWindowPackDown();
 
@@ -346,13 +320,10 @@
     QSignalSpy sizeChangeSpy(shellSurface.data(), &ShellSurface::sizeChanged);
     QVERIFY(sizeChangeSpy.isValid());
     // let's render
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
 
     // let's place it centered
     Placement::self()->placeCentered(c, QRect(0, 0, 1280, 1024));
@@ -391,23 +362,18 @@
     // this test verifies that moving a window through pointer only ends if all buttons are released
     using namespace KWayland::Client;
 
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     QScopedPointer<Surface> surface(Test::createSurface());
     QVERIFY(!surface.isNull());
 
     QScopedPointer<ShellSurface> shellSurface(Test::createShellSurface(surface.data()));
     QVERIFY(!shellSurface.isNull());
     QSignalSpy sizeChangeSpy(shellSurface.data(), &ShellSurface::sizeChanged);
     QVERIFY(sizeChangeSpy.isValid());
     // let's render
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     QVERIFY(c);
+    QCOMPARE(c, workspace()->activeClient());
     QVERIFY(!c->isMove());
 
     // let's trigger the left button
@@ -448,9 +414,6 @@
 {
     // this test verifies that certain window types from PlasmaShellSurface are not moveable or resizable
     using namespace KWayland::Client;
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     QScopedPointer<Surface> surface(Test::createSurface());
     QVERIFY(!surface.isNull());
 
@@ -462,11 +425,8 @@
     QFETCH(KWayland::Client::PlasmaShellSurface::Role, role);
     plasmaSurface->setRole(role);
     // let's render
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = clientAddedSpy.first().first().value<AbstractClient*>();
     QVERIFY(c);
     QTEST(c->isMovable(), "movable");
     QTEST(c->isMovableAcrossScreens(), "movableAcrossScreens");
diff --git a/autotests/integration/plasma_surface_test.cpp b/autotests/integration/plasma_surface_test.cpp
--- a/autotests/integration/plasma_surface_test.cpp
+++ b/autotests/integration/plasma_surface_test.cpp
@@ -103,15 +103,10 @@
     QScopedPointer<PlasmaShellSurface> plasmaSurface(m_plasmaShell->createSurface(surface.data()));
     QVERIFY(!plasmaSurface.isNull());
 
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     // now render to map the window
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
+    AbstractClient *c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
 
     // currently the role is not yet set, so the window should not be on all desktops
     QCOMPARE(c->isOnAllDesktops(), false);
@@ -135,7 +130,7 @@
     QScopedPointer<ShellSurface> shellSurface2(Test::createShellSurface(surface2.data()));
     QVERIFY(!shellSurface2.isNull());
     Test::render(surface2.data(), QSize(100, 50), Qt::blue);
-    QVERIFY(clientAddedSpy.wait());
+    QVERIFY(Test::waitForWaylandWindowShown());
 
     QVERIFY(workspace()->activeClient() != c);
     c = workspace()->activeClient();
@@ -173,14 +168,9 @@
     QFETCH(PlasmaShellSurface::Role, role);
     plasmaSurface->setRole(role);
 
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     // now render to map the window
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
-    QVERIFY(clientAddedSpy.wait());
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    auto c = clientAddedSpy.first().first().value<ShellClient*>();
     QVERIFY(c);
     QTEST(c->wantsInput(), "wantsInput");
     QTEST(c->isActive(), "active");
diff --git a/autotests/integration/quick_tiling_test.cpp b/autotests/integration/quick_tiling_test.cpp
--- a/autotests/integration/quick_tiling_test.cpp
+++ b/autotests/integration/quick_tiling_test.cpp
@@ -131,24 +131,18 @@
 {
     using namespace KWayland::Client;
 
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     QScopedPointer<Surface> surface(Test::createSurface());
     QVERIFY(!surface.isNull());
 
     QScopedPointer<ShellSurface> shellSurface(Test::createShellSurface(surface.data()));
     QVERIFY(!shellSurface.isNull());
     QSignalSpy sizeChangeSpy(shellSurface.data(), &ShellSurface::sizeChanged);
     QVERIFY(sizeChangeSpy.isValid());
     // let's render
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
     QCOMPARE(c->geometry(), QRect(0, 0, 100, 50));
     QCOMPARE(c->quickTileMode(), AbstractClient::QuickTileNone);
     QSignalSpy quickTileChangedSpy(c, &AbstractClient::quickTileModeChanged);
@@ -205,24 +199,18 @@
 {
     using namespace KWayland::Client;
 
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     QScopedPointer<Surface> surface(Test::createSurface());
     QVERIFY(!surface.isNull());
 
     QScopedPointer<ShellSurface> shellSurface(Test::createShellSurface(surface.data()));
     QVERIFY(!shellSurface.isNull());
     QSignalSpy sizeChangeSpy(shellSurface.data(), &ShellSurface::sizeChanged);
     QVERIFY(sizeChangeSpy.isValid());
     // let's render
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
     QCOMPARE(c->geometry(), QRect(0, 0, 100, 50));
     QCOMPARE(c->quickTileMode(), AbstractClient::QuickTileNone);
     QCOMPARE(c->maximizeMode(), MaximizeRestore);
@@ -313,24 +301,18 @@
 {
     using namespace KWayland::Client;
 
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     QScopedPointer<Surface> surface(Test::createSurface());
     QVERIFY(!surface.isNull());
 
     QScopedPointer<ShellSurface> shellSurface(Test::createShellSurface(surface.data()));
     QVERIFY(!shellSurface.isNull());
     QSignalSpy sizeChangeSpy(shellSurface.data(), &ShellSurface::sizeChanged);
     QVERIFY(sizeChangeSpy.isValid());
     // let's render
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
     QCOMPARE(c->geometry(), QRect(0, 0, 100, 50));
     QCOMPARE(c->quickTileMode(), AbstractClient::QuickTileNone);
     QCOMPARE(c->maximizeMode(), MaximizeRestore);
@@ -390,24 +372,18 @@
 {
     using namespace KWayland::Client;
 
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(clientAddedSpy.isValid());
-
     QScopedPointer<Surface> surface(Test::createSurface());
     QVERIFY(!surface.isNull());
 
     QScopedPointer<ShellSurface> shellSurface(Test::createShellSurface(surface.data()));
     QVERIFY(!shellSurface.isNull());
     QSignalSpy sizeChangeSpy(shellSurface.data(), &ShellSurface::sizeChanged);
     QVERIFY(sizeChangeSpy.isValid());
     // let's render
-    Test::render(surface.data(), QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface.data(), QSize(100, 50), Qt::blue);
 
-    m_connection->flush();
-    QVERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     QVERIFY(c);
-    QCOMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    QCOMPARE(workspace()->activeClient(), c);
     QCOMPARE(c->geometry(), QRect(0, 0, 100, 50));
     QCOMPARE(c->quickTileMode(), AbstractClient::QuickTileNone);
     QCOMPARE(c->maximizeMode(), MaximizeRestore);
diff --git a/autotests/integration/struts_test.cpp b/autotests/integration/struts_test.cpp
--- a/autotests/integration/struts_test.cpp
+++ b/autotests/integration/struts_test.cpp
@@ -155,8 +155,6 @@
 
     QFETCH(QVector<QRect>, windowGeometries);
     // create the panels
-    QSignalSpy windowCreatedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(windowCreatedSpy.isValid());
     QHash<Surface*, ShellClient*> clients;
     for (auto it = windowGeometries.constBegin(), end = windowGeometries.constEnd(); it != end; it++) {
         const QRect windowGeometry = *it;
@@ -168,17 +166,13 @@
         plasmaSurface->setRole(PlasmaShellSurface::Role::Panel);
 
         // map the window
-        Test::render(surface, windowGeometry.size(), Qt::red, QImage::Format_RGB32);
+        auto c = Test::renderAndWaitForShown(surface, windowGeometry.size(), Qt::red, QImage::Format_RGB32);
 
-        QVERIFY(windowCreatedSpy.wait());
-        QCOMPARE(windowCreatedSpy.count(), 1);
-        auto c = windowCreatedSpy.first().first().value<ShellClient*>();
         QVERIFY(c);
         QVERIFY(!c->isActive());
         QCOMPARE(c->geometry(), windowGeometry);
         QVERIFY(c->isDock());
         QVERIFY(c->hasStrut());
-        windowCreatedSpy.clear();
         clients.insert(surface, c);
     }
 
@@ -224,21 +218,13 @@
     plasmaSurface->setPosition(windowGeometry.topLeft());
     plasmaSurface->setRole(PlasmaShellSurface::Role::Panel);
 
-    QSignalSpy windowCreatedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(windowCreatedSpy.isValid());
-
     // map the window
-    Test::render(surface.data(), windowGeometry.size(), Qt::red, QImage::Format_RGB32);
-
-    QVERIFY(windowCreatedSpy.wait());
-    QCOMPARE(windowCreatedSpy.count(), 1);
-    auto c = windowCreatedSpy.first().first().value<ShellClient*>();
+    auto c = Test::renderAndWaitForShown(surface.data(), windowGeometry.size(), Qt::red, QImage::Format_RGB32);
     QVERIFY(c);
     QVERIFY(!c->isActive());
     QCOMPARE(c->geometry(), windowGeometry);
     QVERIFY(c->isDock());
     QVERIFY(c->hasStrut());
-    windowCreatedSpy.clear();
     QCOMPARE(workspace()->clientArea(PlacementArea, 0, 1), QRect(0, 0, 1280, 1000));
     QCOMPARE(workspace()->clientArea(MaximizeArea, 0, 1), QRect(0, 0, 1280, 1000));
     QCOMPARE(workspace()->clientArea(PlacementArea, 1, 1), QRect(1280, 0, 1280, 1024));
@@ -276,22 +262,13 @@
     plasmaSurface->setPosition(windowGeometry.topLeft());
     plasmaSurface->setRole(PlasmaShellSurface::Role::Panel);
 
-    QSignalSpy windowCreatedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    QVERIFY(windowCreatedSpy.isValid());
-
     // map the first panel
-    Test::render(surface.data(), windowGeometry.size(), Qt::red, QImage::Format_RGB32);
-
-    QVERIFY(windowCreatedSpy.wait());
-    QCOMPARE(windowCreatedSpy.count(), 1);
-
-    auto c = windowCreatedSpy.first().first().value<ShellClient*>();
+    auto c = Test::renderAndWaitForShown(surface.data(), windowGeometry.size(), Qt::red, QImage::Format_RGB32);
     QVERIFY(c);
     QVERIFY(!c->isActive());
     QCOMPARE(c->geometry(), windowGeometry);
     QVERIFY(c->isDock());
     QVERIFY(c->hasStrut());
-    windowCreatedSpy.clear();
 
     QCOMPARE(workspace()->clientArea(PlacementArea, 0, 1), QRect(0, 60, 1280, 964));
     QCOMPARE(workspace()->clientArea(MaximizeArea, 0, 1), QRect(0, 60, 1280, 964));
@@ -308,18 +285,13 @@
     plasmaSurface2->setPosition(windowGeometry2.topLeft());
     plasmaSurface2->setRole(PlasmaShellSurface::Role::Panel);
 
-    Test::render(surface2.data(), windowGeometry2.size(), Qt::blue, QImage::Format_RGB32);
-
-    QVERIFY(windowCreatedSpy.wait());
-    QCOMPARE(windowCreatedSpy.count(), 1);
+    auto c1 = Test::renderAndWaitForShown(surface2.data(), windowGeometry2.size(), Qt::blue, QImage::Format_RGB32);
 
-    auto c1 = windowCreatedSpy.first().first().value<ShellClient*>();
     QVERIFY(c1);
     QVERIFY(!c1->isActive());
     QCOMPARE(c1->geometry(), windowGeometry2);
     QVERIFY(c1->isDock());
     QVERIFY(c1->hasStrut());
-    windowCreatedSpy.clear();
 
     QCOMPARE(workspace()->clientArea(PlacementArea, 0, 1), QRect(0, 60, 1280, 814));
     QCOMPARE(workspace()->clientArea(MaximizeArea, 0, 1), QRect(0, 60, 1280, 814));
diff --git a/autotests/integration/test_helpers.cpp b/autotests/integration/test_helpers.cpp
--- a/autotests/integration/test_helpers.cpp
+++ b/autotests/integration/test_helpers.cpp
@@ -18,6 +18,8 @@
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *********************************************************************/
 #include "kwin_wayland_test.h"
+#include "shell_client.h"
+#include "wayland_server.h"
 
 #include <KWayland/Client/compositor.h>
 #include <KWayland/Client/connection_thread.h>
@@ -244,6 +246,32 @@
     surface->commit(Surface::CommitFlag::None);
 }
 
+ShellClient *waitForWaylandWindowShown(int timeout)
+{
+    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
+    if (!clientAddedSpy.isValid()) {
+        return nullptr;
+    }
+    if (!clientAddedSpy.wait(timeout)) {
+        return nullptr;
+    }
+    return clientAddedSpy.first().first().value<ShellClient*>();
+}
+
+ShellClient *renderAndWaitForShown(Surface *surface, const QSize &size, const QColor &color, const QImage::Format &format, int timeout)
+{
+    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
+    if (!clientAddedSpy.isValid()) {
+        return nullptr;
+    }
+    render(surface, size, color, format);
+    flushWaylandConnection();
+    if (!clientAddedSpy.wait(timeout)) {
+        return nullptr;
+    }
+    return clientAddedSpy.first().first().value<ShellClient*>();
+}
+
 void flushWaylandConnection()
 {
     if (s_waylandConnection.connection) {
diff --git a/autotests/integration/touch_input_test.cpp b/autotests/integration/touch_input_test.cpp
--- a/autotests/integration/touch_input_test.cpp
+++ b/autotests/integration/touch_input_test.cpp
@@ -100,21 +100,16 @@
 #define COMPARE(actual, expected) \
     if (!QTest::qCompare(actual, expected, #actual, #expected, __FILE__, __LINE__))\
         return nullptr;
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    VERIFY(clientAddedSpy.isValid());
 
     Surface *surface = Test::createSurface(Test::waylandCompositor());
     VERIFY(surface);
     ShellSurface *shellSurface = Test::createShellSurface(surface, surface);
     VERIFY(shellSurface);
     // let's render
-    Test::render(surface, QSize(100, 50), Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface, QSize(100, 50), Qt::blue);
 
-    Test::flushWaylandConnection();
-    VERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     VERIFY(c);
-    COMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    COMPARE(workspace()->activeClient(), c);
 
 #undef VERIFY
 #undef COMPARE
diff --git a/autotests/integration/transient_placement.cpp b/autotests/integration/transient_placement.cpp
--- a/autotests/integration/transient_placement.cpp
+++ b/autotests/integration/transient_placement.cpp
@@ -106,8 +106,6 @@
 #define COMPARE(actual, expected) \
     if (!QTest::qCompare(actual, expected, #actual, #expected, __FILE__, __LINE__))\
         return nullptr;
-    QSignalSpy clientAddedSpy(waylandServer(), &WaylandServer::shellClientAdded);
-    VERIFY(clientAddedSpy.isValid());
 
     Surface *surface = Test::createSurface(Test::waylandCompositor());
     VERIFY(surface);
@@ -126,13 +124,10 @@
         COMPARE(deco->mode(), ServerSideDecoration::Mode::Server);
     }
     // let's render
-    Test::render(surface, size, Qt::blue);
+    auto c = Test::renderAndWaitForShown(surface, size, Qt::blue);
 
-    Test::flushWaylandConnection();
-    VERIFY(clientAddedSpy.wait());
-    AbstractClient *c = workspace()->activeClient();
     VERIFY(c);
-    COMPARE(clientAddedSpy.first().first().value<ShellClient*>(), c);
+    COMPARE(workspace()->activeClient(), c);
 
 #undef VERIFY
 #undef COMPARE