diff --git a/UM/Qt/QtApplication.py b/UM/Qt/QtApplication.py
index cb72d1822..9bbec9879 100644
--- a/UM/Qt/QtApplication.py
+++ b/UM/Qt/QtApplication.py
@@ -457,6 +457,7 @@ def isShuttingDown(self) -> bool:
         return self._is_shutting_down
 
     def registerObjects(self, engine) -> None: #type: ignore #Don't type engine, because the type depends on the platform you're running on so it always gives an error somewhere.
+        engine.rootContext().setContextProperty("QtApplication", self)
         engine.rootContext().setContextProperty("PluginRegistry", PluginRegistry.getInstance())
 
     def makeRenderer(self) -> QtRenderer:
@@ -468,8 +469,6 @@ def getRenderer(self) -> QtRenderer:
 
         return cast(QtRenderer, self._renderer)
 
-    mainWindowChanged = Signal()
-
     def getMainWindow(self) -> Optional[MainWindow]:
         return self._main_window
 
@@ -483,6 +482,9 @@ def setMainWindow(self, window: MainWindow) -> None:
                 self._main_window.windowStateChanged.connect(self._onMainWindowStateChanged)
             self.mainWindowChanged.emit()
 
+    mainWindowChanged = Signal()
+    mainWindow = pyqtProperty(QQuickWindow, fget=getMainWindow, constant=True)
+
     def setVisible(self, visible: bool) -> None:
         if self._main_window is not None:
             self._main_window.visible = visible
@@ -614,7 +616,6 @@ def createQmlSubWindow(self, qml_file_path: str, context_properties: Dict[str, "
         Create a QML window from a QML file. This method uses createQmlComponent internally, but adds a few specific
         features for windows management:
             * The created object is a QQuickWindow instance
-            * The transient parent of the window is explicitly set to be the main window
             * The window ownership is handled and it will be destroyed as soon as it's no longer visible,
               so the caller should not keep a reference to it
         :param qml_file_path: The absolute file path to the root qml file.
@@ -626,9 +627,7 @@ def createQmlSubWindow(self, qml_file_path: str, context_properties: Dict[str, "
         if result is None:
             return None
 
-        result.setTransientParent(self._main_window)
-
-        # Keep a link to the window so that it is not garbage-collected, then register it for destruction
+        # Keep a link to the window so that it is not garbage-collected, then register it for destruction.
         self._sub_windows.append(result)
         result.visibleChanged.connect(self._onWindowVisibleChange, Qt.ConnectionType.QueuedConnection)
 
diff --git a/UM/Qt/qml/UM/Dialog.qml b/UM/Qt/qml/UM/Dialog.qml
index 465905230..13d9374fd 100644
--- a/UM/Qt/qml/UM/Dialog.qml
+++ b/UM/Qt/qml/UM/Dialog.qml
@@ -20,12 +20,13 @@ Window
     minimumHeight: screenScaleFactor * 480;
     width: minimumWidth
     height: minimumHeight
+    transientParent: QtApplication.mainWindow
 
     property int margin: UM.Theme.getSize("default_margin").width
     property bool closeOnAccept: true;  // Automatically close the window when the window is "accepted" (eg using the return key)
     property bool selfDestroy: false;  // Automatically destroys the dialog when it has been hidden, useful if it has been created with component.createObject
 
-    default property alias contents: contentItem.children;
+    default property alias contents: contentItem.data;
 
     property alias loader: contentLoader
 
diff --git a/conandata.yml b/conandata.yml
index 29ece110b..3dcbf38cb 100644
--- a/conandata.yml
+++ b/conandata.yml
@@ -411,10 +411,12 @@ pip_requirements_core:
 
 pip_requirements_dev:
   any_os:
-    pytest: {}
+    pytest:
+      version: "9.1.1"
     twisted:
       version: "21.2.0"
-    pytest-benchmark: {}
+    pytest-benchmark:
+      version: "5.3.0"
     sip: {}
 
 python_translation_source_folders: