diff --git a/src/wayland/server/outputdevice_interface.cpp b/src/wayland/server/outputdevice_interface.cpp
index 4ae68ceafe..f600116853 100644
--- a/src/wayland/server/outputdevice_interface.cpp
+++ b/src/wayland/server/outputdevice_interface.cpp
@@ -136,12 +136,9 @@ OutputDeviceInterface::OutputDeviceInterface(Display *display, QObject *parent)
     Q_D();
     connect(this, &OutputDeviceInterface::currentModeChanged, this,
         [this, d] {
-            auto currentModeIt = std::find_if(d->modes.constBegin(), d->modes.constEnd(), [](const Mode &mode) { return mode.flags.testFlag(ModeFlag::Current); });
-            if (currentModeIt == d->modes.constEnd()) {
-                return;
-            }
+            Q_ASSERT(d->currentMode.id >= 0);
             for (auto it = d->resources.constBegin(); it != d->resources.constEnd(); ++it) {
-                d->sendMode((*it).resource, *currentModeIt);
+                d->sendMode((*it).resource, d->currentMode);
                 d->sendDone(*it);
             }
             wl_display_flush_clients(*(d->display));
@@ -187,9 +184,10 @@ int OutputDeviceInterface::refreshRate() const
 void OutputDeviceInterface::addMode(Mode &mode)
 {
     Q_ASSERT(!isValid());
+    Q_ASSERT(mode.id >= 0);
+    Q_ASSERT(mode.size.isValid());
     Q_D();
 
-
     auto currentModeIt = std::find_if(d->modes.begin(), d->modes.end(),
         [](const Mode &mode) {
             return mode.flags.testFlag(ModeFlag::Current);
diff --git a/src/wayland/server/outputdevice_interface.h b/src/wayland/server/outputdevice_interface.h
index a9424cb671..2d20f0d8b3 100644
--- a/src/wayland/server/outputdevice_interface.h
+++ b/src/wayland/server/outputdevice_interface.h
@@ -132,6 +132,13 @@ public:
     void setSubPixel(SubPixel subPixel);
     void setTransform(Transform transform);
     void setColorCurves(const ColorCurves &colorCurves);
+
+    /**
+     * Add an additional mode to this output device. This is only allowed before create() is called
+     * on the object.
+     *
+     * @param mode must have a valid size and non-negative id.
+     */
     void addMode(Mode &mode);
     void setCurrentMode(const int modeId);