hoverpanel: add max height with flickable scrolling when content overflows

shell/modules/HoverPanel.qml

@@ -373,9 +373,20 @@ PanelWindow {
                 }
             }
 
-            Column {
+            Flickable {
-                id: panelContent
+                id: _flickable
                 width: parent.width
+                height: Math.min(panelContent.height, _maxContentHeight)
+                contentHeight: panelContent.height
+                clip: contentHeight > height
+                boundsBehavior: Flickable.StopAtBounds
+
+                readonly property real _maxContentHeight: (root.screen?.height ?? 1080) * 0.6 - (_headerItem.visible ? _headerItem.height : 0)
+
+                Column {
+                    id: panelContent
+                    width: parent.width
+                }
             }
         }
     }