improve panel background is shown identification

containment/package/contents/ui/PanelBox.qml

@@ -41,6 +41,8 @@ Item{
 
     opacity: root.useThemePanel ? 1 : 0
 
+    readonly property bool isShown: (solidBackground.opacity > 0) || (overlayedBackground.opacity > 0)
+
     property int animationTime: 6*root.durationTime*units.shortDuration
 
     property int lengthMargins: {

containment/package/contents/ui/VisibilityManager.qml

@@ -190,8 +190,7 @@ Item{
             var isTouchingTopScreenEdge = (latteView.y === latteView.screenGeometry.y);
             var hasTopBorder = ((latteView.effects && (latteView.effects.enabledBorders & PlasmaCore.FrameSvg.TopBorder)) > 0);
 
-            return root.isVertical && !latteView.visibility.isHidden && !isTouchingTopScreenEdge && !hasTopBorder
-                    && (root.forcePanelForBusyBackground || root.forceSolidPanel);
+            return root.isVertical && !latteView.visibility.isHidden && !isTouchingTopScreenEdge && !hasTopBorder && panelBoxBackground.isShown;
         }
     }
 
@@ -206,8 +205,7 @@ Item{
 
             var hasBottomBorder = ((latteView.effects && (latteView.effects.enabledBorders & PlasmaCore.FrameSvg.BottomBorder)) > 0);
 
-            return root.isVertical && !latteView.visibility.isHidden && !isTouchingBottomScreenEdge && !hasBottomBorder
-                    && (root.forcePanelForBusyBackground || root.forceSolidPanel);
+            return root.isVertical && !latteView.visibility.isHidden && !isTouchingBottomScreenEdge && !hasBottomBorder && panelBoxBackground.isShown;
         }
     }