Monitor Tab - Camera button toggles

Contributes to CL-1049

plugins/UM3NetworkPrinting/resources/qml/ClusterControlItem.qml

@@ -651,6 +651,12 @@ Component
                                         anchors.fill:parent
                                         hoverEnabled: true
                                         onClicked:
+                                        {
+                                            if (OutputDevice.activeCamera !== null)
+                                            {
+                                                OutputDevice.setActiveCamera(null)
+                                            }
+                                            else
                                             {
                                                 OutputDevice.setActiveCamera(modelData.camera)
                                             }
@@ -658,6 +664,7 @@ Component
                                     }
                                 }
                             }
+                        }
 
                         ProgressBar
                         {