diff --git a/CMakeLists.txt b/CMakeLists.txt
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -27,7 +27,7 @@
 
 # Dependencies
 set(REQUIRED_QT_VERSION 5.5.0)
-find_package(Qt5 ${REQUIRED_QT_VERSION} CONFIG REQUIRED Gui)
+find_package(Qt5 ${REQUIRED_QT_VERSION} CONFIG REQUIRED Concurrent Gui)
 
 find_package(Wayland 1.7 COMPONENTS Client Server)
 set_package_properties(Wayland PROPERTIES
diff --git a/autotests/client/test_wayland_windowmanagement.cpp b/autotests/client/test_wayland_windowmanagement.cpp
--- a/autotests/client/test_wayland_windowmanagement.cpp
+++ b/autotests/client/test_wayland_windowmanagement.cpp
@@ -66,6 +66,7 @@
     void testRequestShowingDesktop();
     void testParentWindow();
     void testGeometry();
+    void testIcon();
 
     void cleanup();
 
@@ -545,5 +546,40 @@
     QCOMPARE(window->geometry(), QRect(0, 0, 35, 45));
 }
 
-QTEST_GUILESS_MAIN(TestWindowManagement)
+void TestWindowManagement::testIcon()
+{
+    using namespace KWayland::Client;
+    QVERIFY(m_window);
+    QSignalSpy iconChangedSpy(m_window, &PlasmaWindow::iconChanged);
+    QVERIFY(iconChangedSpy.isValid());
+    m_windowInterface->setIcon(QIcon());
+    // first goes from themed name to empty
+    QVERIFY(iconChangedSpy.wait());
+    if (!QIcon::hasThemeIcon(QStringLiteral("wayland"))) {
+        QEXPECT_FAIL("", "no icon", Continue);
+    }
+    QCOMPARE(m_window->icon().name(), QStringLiteral("wayland"));
+    QVERIFY(iconChangedSpy.wait());
+    if (!QIcon::hasThemeIcon(QStringLiteral("wayland"))) {
+        QEXPECT_FAIL("", "no icon", Continue);
+    }
+    QCOMPARE(m_window->icon().name(), QStringLiteral("wayland"));
+
+    // create an icon with a pixmap
+    QPixmap p(32, 32);
+    p.fill(Qt::red);
+    m_windowInterface->setIcon(p);
+    QVERIFY(iconChangedSpy.wait());
+    QCOMPARE(m_window->icon().pixmap(32, 32), p);
+
+    // let's set a themed icon
+    m_windowInterface->setIcon(QIcon::fromTheme(QStringLiteral("xorg")));
+    QVERIFY(iconChangedSpy.wait());
+    if (!QIcon::hasThemeIcon(QStringLiteral("xorg"))) {
+        QEXPECT_FAIL("", "no icon", Continue);
+    }
+    QCOMPARE(m_window->icon().name(), QStringLiteral("xorg"));
+}
+
+QTEST_MAIN(TestWindowManagement)
 #include "test_wayland_windowmanagement.moc"
diff --git a/src/client/CMakeLists.txt b/src/client/CMakeLists.txt
--- a/src/client/CMakeLists.txt
+++ b/src/client/CMakeLists.txt
@@ -143,6 +143,7 @@
 target_link_libraries(KF5WaylandClient
     PUBLIC Qt5::Gui
     PRIVATE Wayland::Client
+        Qt5::Concurrent
 )
 
 if(IS_ABSOLUTE "${KF5_INCLUDE_INSTALL_DIR}")
diff --git a/src/client/plasmawindowmanagement.cpp b/src/client/plasmawindowmanagement.cpp
--- a/src/client/plasmawindowmanagement.cpp
+++ b/src/client/plasmawindowmanagement.cpp
@@ -26,7 +26,10 @@
 // Wayland
 #include <wayland-plasma-window-management-client-protocol.h>
 
+#include <QtConcurrentRun>
+#include <QFutureWatcher>
 #include <QTimer>
+#include <qplatformdefs.h>
 
 namespace KWayland
 {
@@ -99,6 +102,7 @@
     static void initialStateCallback(void *data, org_kde_plasma_window *window);
     static void parentWindowCallback(void *data, org_kde_plasma_window *window, org_kde_plasma_window *parent);
     static void windowGeometryCallback(void *data, org_kde_plasma_window *window, int32_t x, int32_t y, uint32_t width, uint32_t height);
+    static void iconChangedCallback(void *data, org_kde_plasma_window *org_kde_plasma_window);
     void setActive(bool set);
     void setMinimized(bool set);
     void setMaximized(bool set);
@@ -334,7 +338,8 @@
     unmappedCallback,
     initialStateCallback,
     parentWindowCallback,
-    windowGeometryCallback
+    windowGeometryCallback,
+    iconChangedCallback
 };
 
 void PlasmaWindow::Private::parentWindowCallback(void *data, org_kde_plasma_window *window, org_kde_plasma_window *parent)
@@ -473,6 +478,64 @@
     emit p->q->iconChanged();
 }
 
+static int readData(int fd, QByteArray &data)
+{
+    // implementation based on QtWayland file qwaylanddataoffer.cpp
+    char buf[4096];
+    int retryCount = 0;
+    int n;
+    while (true) {
+        n = QT_READ(fd, buf, sizeof buf);
+        if (n == -1 && (errno == EAGAIN) && ++retryCount < 1000) {
+            usleep(1000);
+        } else {
+            break;
+        }
+    }
+    if (n > 0) {
+        data.append(buf, n);
+        n = readData(fd, data);
+    }
+    return n;
+}
+
+void PlasmaWindow::Private::iconChangedCallback(void *data, org_kde_plasma_window *window)
+{
+    auto p = cast(data);
+    Q_UNUSED(window);
+    int pipeFds[2];
+    if (pipe2(pipeFds, O_CLOEXEC|O_NONBLOCK) != 0) {
+        return;
+    }
+    org_kde_plasma_window_get_icon(p->window, pipeFds[1]);
+    close(pipeFds[1]);
+    const int pipeFd = pipeFds[0];
+    auto readIcon = [pipeFd] () -> QIcon {
+        QByteArray content;
+        if (readData(pipeFd, content) != 0) {
+            close(pipeFd);
+            return QIcon::fromTheme(QStringLiteral("wayland"));
+        }
+        close(pipeFd);
+        QDataStream ds(content);
+        QIcon icon;
+        ds >> icon;
+        if (icon.isNull()) {
+            return QIcon::fromTheme(QStringLiteral("wayland"));
+        }
+        return icon;
+    };
+    QFutureWatcher<QIcon> *watcher = new QFutureWatcher<QIcon>(p->q);
+    QObject::connect(watcher, &QFutureWatcher<QIcon>::finished, p->q,
+        [p, watcher] {
+            watcher->deleteLater();
+            p->icon = watcher->result();
+            emit p->q->iconChanged();
+        }
+    );
+    watcher->setFuture(QtConcurrent::run(readIcon));
+}
+
 void PlasmaWindow::Private::setActive(bool set)
 {
     if (active == set) {
diff --git a/src/client/protocols/plasma-window-management.xml b/src/client/protocols/plasma-window-management.xml
--- a/src/client/protocols/plasma-window-management.xml
+++ b/src/client/protocols/plasma-window-management.xml
@@ -17,7 +17,7 @@
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
   ]]></copyright>
 
-  <interface name="org_kde_plasma_window_management" version="6">
+  <interface name="org_kde_plasma_window_management" version="7">
     <description summary="application windows management">
       This interface manages application windows.
       It provides requests to show and hide the desktop and emits
@@ -83,7 +83,7 @@
     </event>
   </interface>
 
-  <interface name="org_kde_plasma_window" version="6">
+  <interface name="org_kde_plasma_window" version="7">
     <description summary="interface to control application windows">
       Manages and control an application window.
 
@@ -164,6 +164,14 @@
       </description>
     </request>
 
+    <request name="get_icon" since="7">
+      <description summary="Requests to get the window icon">
+        The compositor will write the window icon into the provided file descriptor.
+        The data is a serialized QIcon with QDataStream.
+      </description>
+      <arg name="fd" type="fd" summary="file descriptor for the icon"/>
+    </request>
+
     <event name="title_changed">
       <description summary="window title has been changed">
         This event will be sent as soon as the window title is changed.
@@ -240,5 +248,14 @@
         <arg name="width" type="uint" summary="width of the org_kde_plasma_window"/>
         <arg name="height" type="uint" summary="height of the org_kde_plasma_window"/>
     </event>
+
+    <event name="icon_changed" since="7">
+        <description summary="The icon of the window changed">
+            This event will be sent whenever the icon of the window changes, but there is no themed
+            icon name. Common examples are Xwayland windows which have a pixmap based icon.
+
+            The client can request the icon using get_icon.
+        </description>
+    </event>
   </interface>
 </protocol>
diff --git a/src/client/registry.cpp b/src/client/registry.cpp
--- a/src/client/registry.cpp
+++ b/src/client/registry.cpp
@@ -153,7 +153,7 @@
         &Registry::plasmaShellRemoved
     }},
     {Registry::Interface::PlasmaWindowManagement, {
-        6,
+        7,
         QByteArrayLiteral("org_kde_plasma_window_management"),
         &org_kde_plasma_window_management_interface,
         &Registry::plasmaWindowManagementAnnounced,
diff --git a/src/server/CMakeLists.txt b/src/server/CMakeLists.txt
--- a/src/server/CMakeLists.txt
+++ b/src/server/CMakeLists.txt
@@ -145,6 +145,7 @@
     PRIVATE
         Wayland::Server
         EGL::EGL
+        Qt5::Concurrent
 )
 
 if(IS_ABSOLUTE "${KF5_INCLUDE_INSTALL_DIR}")
diff --git a/src/server/plasmawindowmanagement_interface.h b/src/server/plasmawindowmanagement_interface.h
--- a/src/server/plasmawindowmanagement_interface.h
+++ b/src/server/plasmawindowmanagement_interface.h
@@ -101,7 +101,13 @@
     void setMaximizeable(bool set);
     void setFullscreenable(bool set);
     void setSkipTaskbar(bool skip);
-    void setThemedIconName(const QString &iconName);
+    /**
+     * @deprecated since 5.28 use setIcon
+     * @see setIcon
+     **/
+#ifndef KWAYLANDSERVER_NO_DEPRECATED
+    void KWAYLANDSERVER_DEPRECATED setThemedIconName(const QString &iconName);
+#endif
     /**
      * @since 5.22
      */
@@ -155,6 +161,19 @@
      **/
     void setGeometry(const QRect &geometry);
 
+    /**
+     * Set the icon of the PlasmaWindowInterface.
+     *
+     * In case the icon has a themed name, only the name is sent to the client.
+     * Otherwise the client is only informed that there is an icon and the client
+     * can request the icon in an asynchronous way by passing a file descriptor
+     * into which the icon will be serialized.
+     *
+     * @param icon The new icon
+     * @since 5.28
+     **/
+    void setIcon(const QIcon &icon);
+
 Q_SIGNALS:
     void closeRequested();
     /**
diff --git a/src/server/plasmawindowmanagement_interface.cpp b/src/server/plasmawindowmanagement_interface.cpp
--- a/src/server/plasmawindowmanagement_interface.cpp
+++ b/src/server/plasmawindowmanagement_interface.cpp
@@ -23,6 +23,9 @@
 #include "display.h"
 #include "surface_interface.h"
 
+#include <QtConcurrentRun>
+#include <QFile>
+#include <QIcon>
 #include <QList>
 #include <QVector>
 #include <QRect>
@@ -70,6 +73,7 @@
     void setTitle(const QString &title);
     void setAppId(const QString &appId);
     void setThemedIconName(const QString &iconName);
+    void setIcon(const QIcon &icon);
     void setVirtualDesktop(quint32 desktop);
     void unmap();
     void setState(org_kde_plasma_window_management_state flag, bool set);
@@ -97,21 +101,23 @@
     static void setMinimizedGeometryCallback(wl_client *client, wl_resource *resource, wl_resource *panel, uint32_t x, uint32_t y, uint32_t width, uint32_t height);
     static void unsetMinimizedGeometryCallback(wl_client *client, wl_resource *resource, wl_resource *panel);
     static void destroyCallback(wl_client *client, wl_resource *resource);
+    static void getIconCallback(wl_client *client, wl_resource *resource, int32_t fd);
     static Private *cast(wl_resource *resource) {
         return reinterpret_cast<Private*>(wl_resource_get_user_data(resource));
     }
 
     PlasmaWindowInterface *q;
     QString m_title;
     QString m_appId;
     QString m_themedIconName;
+    QIcon m_icon;
     quint32 m_virtualDesktop = 0;
     quint32 m_state = 0;
     wl_listener listener;
     static const struct org_kde_plasma_window_interface s_interface;
 };
 
-const quint32 PlasmaWindowManagementInterface::Private::s_version = 6;
+const quint32 PlasmaWindowManagementInterface::Private::s_version = 7;
 
 PlasmaWindowManagementInterface::Private::Private(PlasmaWindowManagementInterface *q, Display *d)
     : Global::Private(d, &org_kde_plasma_window_management_interface, s_version)
@@ -267,7 +273,8 @@
     closeCallback,
     requestMoveCallback,
     requestResizeCallback,
-    destroyCallback
+    destroyCallback,
+    getIconCallback
 };
 #endif
 
@@ -326,7 +333,13 @@
         org_kde_plasma_window_send_title_changed(resource, m_title.toUtf8().constData());
     }
     org_kde_plasma_window_send_state_changed(resource, m_state);
-    org_kde_plasma_window_send_themed_icon_name_changed(resource, m_themedIconName.toUtf8().constData());
+    if (!m_themedIconName.isEmpty()) {
+        org_kde_plasma_window_send_themed_icon_name_changed(resource, m_themedIconName.toUtf8().constData());
+    } else {
+        if (wl_resource_get_version(resource) >= ORG_KDE_PLASMA_WINDOW_ICON_CHANGED_SINCE_VERSION) {
+            org_kde_plasma_window_send_icon_changed(resource);
+        }
+    }
 
     org_kde_plasma_window_send_parent_window(resource, resourceForParent(parentWindow, resource));
 
@@ -368,6 +381,34 @@
     }
 }
 
+void PlasmaWindowInterface::Private::setIcon(const QIcon &icon)
+{
+    m_icon = icon;
+    setThemedIconName(m_icon.name());
+    if (m_icon.name().isEmpty()) {
+        for (auto it = resources.constBegin(); it != resources.constEnd(); ++it) {
+            if (wl_resource_get_version(*it) >= ORG_KDE_PLASMA_WINDOW_ICON_CHANGED_SINCE_VERSION) {
+                org_kde_plasma_window_send_icon_changed(*it);
+            }
+        }
+    }
+}
+
+void PlasmaWindowInterface::Private::getIconCallback(wl_client *client, wl_resource *resource, int32_t fd)
+{
+    Q_UNUSED(client)
+    Private *p = cast(resource);
+    QtConcurrent::run(
+        [fd] (const QIcon &icon) {
+            QFile file;
+            file.open(fd, QIODevice::WriteOnly, QFileDevice::AutoCloseHandle);
+            QDataStream ds(&file);
+            ds << icon;
+            file.close();
+        }, p->m_icon
+    );
+}
+
 void PlasmaWindowInterface::Private::setTitle(const QString &title)
 {
     if (m_title == title) {
@@ -699,10 +740,17 @@
     d->setState(ORG_KDE_PLASMA_WINDOW_MANAGEMENT_STATE_SKIPTASKBAR, set);
 }
 
+#ifndef KWAYLANDSERVER_NO_DEPRECATED
 void PlasmaWindowInterface::setThemedIconName(const QString &iconName)
 {
     d->setThemedIconName(iconName);
 }
+#endif
+
+void PlasmaWindowInterface::setIcon(const QIcon &icon)
+{
+    d->setIcon(icon);
+}
 
 void PlasmaWindowInterface::setShadeable(bool set)
 {
diff --git a/src/tools/CMakeLists.txt b/src/tools/CMakeLists.txt
--- a/src/tools/CMakeLists.txt
+++ b/src/tools/CMakeLists.txt
@@ -2,14 +2,9 @@
 
 include(ECMMarkAsTest)
 
-find_package(Qt5Concurrent ${QT_MIN_VERSION} CONFIG QUIET)
+set(scannerSRCS generator.cpp)
 
-if (Qt5Concurrent_FOUND)
-    set(scannerSRCS generator.cpp)
-
-    add_definitions(-DMAPPING_FILE="${CMAKE_CURRENT_SOURCE_DIR}/mapping.txt")
-    add_executable(kwaylandScanner ${scannerSRCS})
-    target_link_libraries(kwaylandScanner Qt5::Core Qt5::Concurrent)
-    ecm_mark_as_test(kwaylandScanner)
-
-endif()
+add_definitions(-DMAPPING_FILE="${CMAKE_CURRENT_SOURCE_DIR}/mapping.txt")
+add_executable(kwaylandScanner ${scannerSRCS})
+target_link_libraries(kwaylandScanner Qt5::Core Qt5::Concurrent)
+ecm_mark_as_test(kwaylandScanner)
diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -10,8 +10,7 @@
 ecm_mark_as_test(testServer)
 
 find_package(Qt5Widgets ${QT_MIN_VERSION} CONFIG QUIET)
-find_package(Qt5Concurrent ${QT_MIN_VERSION} CONFIG QUIET)
-if (Qt5Widgets_FOUND AND Qt5Concurrent_FOUND)
+if (Qt5Widgets_FOUND)
     set(testRenderingServer_SRCS
         renderingservertest.cpp
         )
@@ -24,11 +23,9 @@
 target_link_libraries(copyClient KF5::WaylandClient)
 ecm_mark_as_test(copyClient)
 
-if (Qt5Concurrent_FOUND)
-    add_executable(pasteClient pasteclient.cpp)
-    target_link_libraries(pasteClient Qt5::Concurrent KF5::WaylandClient)
-    ecm_mark_as_test(pasteClient)
-endif()
+add_executable(pasteClient pasteclient.cpp)
+target_link_libraries(pasteClient Qt5::Concurrent KF5::WaylandClient)
+ecm_mark_as_test(pasteClient)
 
 if (HAVE_LINUX_INPUT_H)
     add_executable(touchClientTest touchclienttest.cpp)