diff --git a/applets/systemtray/package/contents/ui/main.qml b/applets/systemtray/package/contents/ui/main.qml
--- a/applets/systemtray/package/contents/ui/main.qml
+++ b/applets/systemtray/package/contents/ui/main.qml
@@ -39,7 +39,7 @@
     property var iconSizes: ["small", "smallMedium", "medium", "large", "huge", "enormous"];
 
     property bool vertical: plasmoid.formFactor == PlasmaCore.Types.Vertical
-    property int itemSize: units.roundToIconSize(Math.min(Math.min(width, height), units.iconSizes[iconSizes[plasmoid.configuration.iconSize]]))
+    property int itemSize: Math.min(0.8 * width, 0.8 * height, units.iconSizeHints.panel)
     property int hiddenItemSize: units.iconSizes.smallMedium
     property alias expanded: dialog.visible
     property Item activeApplet