SmartPanelWindow: add a small delay in an attempt to improve cleanup

Modules/MainScreen/SmartPanelWindow.qml

@@ -47,6 +47,9 @@ PanelWindow {
   property bool closeWatchdogActive: false
   property bool openWatchdogActive: false
 
+  // Delay before unloading content (helps with shader cleanup on older Qt versions)
+  property int contentUnloadDelay: 100
+
   // Signals
   signal panelOpened
   signal panelClosed
@@ -176,13 +179,21 @@ PanelWindow {
     closeWatchdogTimer.stop();
 
     root.isPanelVisible = false;
+
+    // Delay unloading content to ensure shaders are properly cleaned up (helps with older Qt versions)
+    contentUnloadDelayTimer.start();
+
+    Logger.d("SmartPanelWindow", "Panel close finalized, delaying content unload", placeholder.panelName);
+  }
+
+  function completeContentUnload() {
     root.isPanelOpen = false;
     root.isClosing = false;
     root.opacityFadeComplete = false;
     PanelService.closedPanel(root);
     panelClosed();
 
-    Logger.d("SmartPanelWindow", "Panel close finalized", placeholder.panelName);
+    Logger.d("SmartPanelWindow", "Content unloaded", placeholder.panelName);
   }
 
   // Fullscreen container for click-to-close and content
@@ -433,6 +444,16 @@ PanelWindow {
     }
   }
 
+  // Timer to delay content unloading after panel closes (helps with shader cleanup on older Qt)
+  Timer {
+    id: contentUnloadDelayTimer
+    interval: root.contentUnloadDelay
+    repeat: false
+    onTriggered: {
+      root.completeContentUnload();
+    }
+  }
+
   // Watch for placeholder size animation completion to finalize close
   Connections {
     target: placeholder.panelItem