diff --git a/cura/PrinterOutput/PrinterOutputModel.py b/cura/PrinterOutput/PrinterOutputModel.py
index f82d568e63..4189b9fcbd 100644
--- a/cura/PrinterOutput/PrinterOutputModel.py
+++ b/cura/PrinterOutput/PrinterOutputModel.py
@@ -49,17 +49,21 @@ class PrinterOutputModel(QObject):
         self._printer_configuration.extruderConfigurations = [extruder.extruderConfiguration for extruder in
                                                               self._extruders]
 
-        self._camera_url = None  # type: Optional[QUrl]
+        self._camera_url = QUrl()  # type: QUrl
 
     @pyqtProperty(str, constant = True)
     def firmwareVersion(self) -> str:
         return self._firmware_version
 
-    def setCameraUrl(self, camera_url: Optional["QUrl"]) -> None:
-        if self._camera_url is not camera_url:
+    def setCameraUrl(self, camera_url: "QUrl") -> None:
+        if self._camera_url != camera_url:
             self._camera_url = camera_url
             self.cameraUrlChanged.emit()
 
+    @pyqtProperty(QUrl, fset = setCameraUrl, notify = cameraUrlChanged)
+    def cameraUrl(self) -> "QUrl":
+        return self._camera_url
+
     def updateIsPreheating(self, pre_heating: bool) -> None:
         if self._is_preheating != pre_heating:
             self._is_preheating = pre_heating
@@ -69,10 +73,6 @@ class PrinterOutputModel(QObject):
     def isPreheating(self) -> bool:
         return self._is_preheating
 
-    @pyqtProperty(QUrl, notify=cameraUrlChanged)
-    def cameraUrl(self) -> Optional["QUrl"]:
-        return self._camera_url
-
     @pyqtProperty(str, notify = printerTypeChanged)
     def type(self) -> str:
         return self._printer_type
diff --git a/plugins/UM3NetworkPrinting/resources/qml/CameraButton.qml b/plugins/UM3NetworkPrinting/resources/qml/CameraButton.qml
index 7ec0cb880a..7e5c254e5c 100644
--- a/plugins/UM3NetworkPrinting/resources/qml/CameraButton.qml
+++ b/plugins/UM3NetworkPrinting/resources/qml/CameraButton.qml
@@ -31,8 +31,8 @@ Rectangle {
         anchors.fill: parent;
         hoverEnabled: true;
         onClicked: {
-            if (OutputDevice.activeCameraUrl !== null) {
-                OutputDevice.setActiveCameraUrl(null)
+            if (OutputDevice.activeCameraUrl != "") {
+                OutputDevice.setActiveCameraUrl("");
             } else {
                 OutputDevice.setActiveCameraUrl(modelData.cameraUrl);
             }
diff --git a/plugins/UM3NetworkPrinting/resources/qml/ClusterMonitorItem.qml b/plugins/UM3NetworkPrinting/resources/qml/ClusterMonitorItem.qml
index a9166432ae..d210ab40f3 100644
--- a/plugins/UM3NetworkPrinting/resources/qml/ClusterMonitorItem.qml
+++ b/plugins/UM3NetworkPrinting/resources/qml/ClusterMonitorItem.qml
@@ -16,7 +16,7 @@ Component {
         height: maximumHeight;
         onVisibleChanged: {
             if (monitorFrame != null && !monitorFrame.visible) {
-                OutputDevice.setActiveCameraUrl(null);
+                OutputDevice.setActiveCameraUrl("");
             }
         }
         width: maximumWidth;
@@ -126,7 +126,7 @@ Component {
         PrinterVideoStream {
             anchors.fill: parent;
             cameraUrl: OutputDevice.activeCameraUrl;
-            visible: OutputDevice.activeCameraUrl != null;
+            visible: OutputDevice.activeCameraUrl != "";
         }
     }
 }
diff --git a/plugins/UM3NetworkPrinting/resources/qml/PrinterVideoStream.qml b/plugins/UM3NetworkPrinting/resources/qml/PrinterVideoStream.qml
index 9b79a8d008..77b481f6d8 100644
--- a/plugins/UM3NetworkPrinting/resources/qml/PrinterVideoStream.qml
+++ b/plugins/UM3NetworkPrinting/resources/qml/PrinterVideoStream.qml
@@ -8,7 +8,7 @@ import UM 1.3 as UM
 import Cura 1.0 as Cura
 
 Item {
-    property var cameraUrl: null;
+    property var cameraUrl: "";
 
     Rectangle {
         anchors.fill:parent;
@@ -18,7 +18,7 @@ Item {
 
     MouseArea {
         anchors.fill: parent;
-        onClicked: OutputDevice.setActiveCameraUrl(null);
+        onClicked: OutputDevice.setActiveCameraUrl("");
         z: 0;
     }
 
@@ -41,11 +41,11 @@ Item {
         height: Math.round((imageHeight === 0 ? 600 * screenScaleFactor : imageHeight) * width / imageWidth);
         onVisibleChanged: {
             if (visible) {
-                if (cameraUrl != null) {
+                if (cameraUrl != "") {
                     start();
                 }
             } else {
-                if (cameraUrl != null) {
+                if (cameraUrl != "") {
                     stop();
                 }
             }
@@ -58,7 +58,7 @@ Item {
     MouseArea {
         anchors.fill: cameraImage;
         onClicked: {
-            OutputDevice.setActiveCameraUrl(null);
+            OutputDevice.setActiveCameraUrl("");
         }
         z: 1;
     }
diff --git a/plugins/UM3NetworkPrinting/src/ClusterUM3OutputDevice.py b/plugins/UM3NetworkPrinting/src/ClusterUM3OutputDevice.py
index 368273102b..7504d55ad9 100644
--- a/plugins/UM3NetworkPrinting/src/ClusterUM3OutputDevice.py
+++ b/plugins/UM3NetworkPrinting/src/ClusterUM3OutputDevice.py
@@ -99,7 +99,7 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
         self._latest_reply_handler = None  # type: Optional[QNetworkReply]
         self._sending_job = None
 
-        self._active_camera_url = None # type: Optional[QUrl]
+        self._active_camera_url = QUrl()  # type: QUrl
 
     def requestWrite(self, nodes: List[SceneNode], file_name: Optional[str] = None, limit_mimetypes: bool = False, file_handler: Optional[FileHandler] = None, **kwargs: str) -> None:
         self.writeStarted.emit(self)
@@ -263,27 +263,20 @@ class ClusterUM3OutputDevice(NetworkedPrinterOutputDevice):
     def activePrinter(self) -> Optional[PrinterOutputModel]:
         return self._active_printer
 
-    @pyqtProperty(QUrl, notify=activeCameraUrlChanged)
-    def activeCameraUrl(self) -> Optional[QUrl]:
-        return self._active_camera_url
-
     @pyqtSlot(QObject)
     def setActivePrinter(self, printer: Optional[PrinterOutputModel]) -> None:
         if self._active_printer != printer:
             self._active_printer = printer
             self.activePrinterChanged.emit()
 
-    @pyqtSlot(QObject)
-    def setActiveCameraUrl(self, camera_url: Optional[QUrl]) -> None:
+    @pyqtProperty(QUrl, notify = activeCameraUrlChanged)
+    def activeCameraUrl(self) -> "QUrl":
+        return self._active_camera_url
+
+    @pyqtSlot(QUrl)
+    def setActiveCameraUrl(self, camera_url: "QUrl") -> None:
         if self._active_camera_url != camera_url:
-            if self._active_camera_url:
-                self._active_camera_url.stop()
-
             self._active_camera_url = camera_url
-
-            if self._active_camera_url:
-                self._active_camera_url.start()
-
             self.activeCameraUrlChanged.emit()
 
     def _onPostPrintJobFinished(self, reply: QNetworkReply) -> None: