diff --git a/panels/dock/pluginmanagerextension.cpp b/panels/dock/pluginmanagerextension.cpp
index 79f198cb9..96b3b75c1 100644
--- a/panels/dock/pluginmanagerextension.cpp
+++ b/panels/dock/pluginmanagerextension.cpp
@@ -44,7 +44,7 @@ void PluginScaleManager::setPluginScale(const uint32_t &scale)
     auto outputs = m_compositor->outputs();
     std::for_each(outputs.begin(), outputs.end(), [this](auto *output) {
         // 120 is base of fractional scale.
-        output->setScaleFactor(std::ceil(m_scale / 120));
+        output->setScaleFactor(std::ceil(m_scale / 120.0));
     });
 
     Q_EMIT pluginScaleChanged(m_scale);
@@ -64,7 +64,7 @@ void PluginScaleManager::initialize()
     init(compositor->display(), 1);
     m_compositor = compositor;
     connect(compositor, &QWaylandCompositor::outputAdded, this, [this](auto *output) {
-        output->setScaleFactor(std::ceil(m_scale / 120));
+        output->setScaleFactor(std::ceil(m_scale / 120.0));
     });
 }
 
diff --git a/panels/dock/tray/ShellSurfaceItemProxy.qml b/panels/dock/tray/ShellSurfaceItemProxy.qml
index 233b034e5..a4d406d4f 100644
--- a/panels/dock/tray/ShellSurfaceItemProxy.qml
+++ b/panels/dock/tray/ShellSurfaceItemProxy.qml
@@ -6,6 +6,7 @@ import QtQuick
 import QtQuick.Controls
 import QtWayland.Compositor
 import org.deepin.ds.dock 1.0
+import org.deepin.ds 1.0
 
 Item {
     id: root
@@ -21,9 +22,19 @@ Item {
 
     ShellSurfaceItem {
         id: impl
-        anchors.fill: parent
+        width: parent.width
+        height: parent.height
         shellSurface: root.shellSurface
         inputEventsEnabled: root.inputEventsEnabled
+        // we need to set smooth to false, otherwise the image
+        // will be blurred if the scale is 1.25.
+        // If the surface width is 150, the buffer width will be 150 * 1.25 = 188
+        // But the ShellSurfaceItem pixel width on screen is 150 * 1.25 = 187.5
+        // So Qt will use the 188 to scale to 187.5, which will be blurred.
+        // But if we set smooth to false, the Qt doesn't linear interpolation.
+        // TODO: If the buffer size greater than the ShellSurfaceItem pixel
+        // size, we also need enable smooth.
+        smooth: false
 
         HoverHandler {
             id: hoverHandler
@@ -33,6 +44,10 @@ Item {
         }
 
         onVisibleChanged: function () {
+            if (visible) {
+                fixPositionTimer.start()
+            }
+
             if (autoClose && !visible) {
                 // surface is valid but client's shellSurface maybe invalid.
                 Qt.callLater(closeShellSurface)
@@ -44,6 +59,37 @@ Item {
                 DockCompositor.closeShellSurface(shellSurface)
             }
         }
+
+        function mapToScene(x, y) {
+            const point = Qt.point(x, y)
+            // Must use parent.mapFoo, because the impl's position is relative to the parent Item
+            const mappedPoint = parent.mapToItem(Window.window.contentItem, point)
+            return mappedPoint
+        }
+
+        function mapFromScene(x, y) {
+            const point = Qt.point(x, y)
+            // Must use parent.mapFoo, because the impl's position is relative to the parent Item
+            const mappedPoint = parent.mapFromItem(Window.window.contentItem, point)
+            return mappedPoint
+        }
+
+        function fixPosition() {
+            // See QTBUG: https://bugreports.qt.io/browse/QTBUG-135833
+            // TODO: should get the devicePixelRatio from the Window
+            x = mapFromScene(Math.ceil(mapToScene(0, 0).x * Panel.devicePixelRatio) / Panel.devicePixelRatio, 0).x
+            y = mapFromScene(0, Math.ceil(mapToScene(0, 0).y * Panel.devicePixelRatio) / Panel.devicePixelRatio).y
+        }
+
+        Timer {
+            id: fixPositionTimer
+            interval: 100
+            repeat: false
+            running: false
+            onTriggered: {
+                impl.fixPosition()
+            }
+        }
     }
     Component.onCompleted: function () {
         impl.surfaceDestroyed.connect(root.surfaceDestroyed)
diff --git a/shell/main.cpp b/shell/main.cpp
index 271355035..908590da7 100644
--- a/shell/main.cpp
+++ b/shell/main.cpp
@@ -96,6 +96,8 @@ int main(int argc, char *argv[])
     setenv("DSG_APP_ID", "org.deepin.dde.shell", 0);
     DGuiApplicationHelper::setAttribute(DGuiApplicationHelper::UseInactiveColorGroup, false);
     QApplication a(argc, argv);
+    // Don't apply to plugins
+    qunsetenv("QT_SCALE_FACTOR");
     // dde-shell contains UI controls based on QML and Widget technologies.
     // Due to the inconsistency of the default font rendering methods of different schemes,
     // the font effects are not uniform.