diff --git a/frame/dbus/dbusdockentry.h b/frame/dbus/dbusdockentry.h
index 4dbb64066..238a639f7 100644
--- a/frame/dbus/dbusdockentry.h
+++ b/frame/dbus/dbusdockentry.h
@@ -121,6 +121,11 @@ public Q_SLOTS: // METHODS
         return asyncCall(QStringLiteral("RequestDock"));
     }
 
+    inline QDBusPendingReply<> Check()
+    {
+        return asyncCall(QStringLiteral("Check"));
+    }
+
     inline QDBusPendingReply<> RequestUndock()
     {
         return asyncCall(QStringLiteral("RequestUndock"));
diff --git a/frame/item/appitem.cpp b/frame/item/appitem.cpp
index 9e07b137d..c90efee2e 100644
--- a/frame/item/appitem.cpp
+++ b/frame/item/appitem.cpp
@@ -4,6 +4,9 @@
 #include "util/imagefactory.h"
 #include "xcb/xcb_misc.h"
 
+#include <X11/X.h>
+#include <X11/Xlib.h>
+
 #include <QPainter>
 #include <QDrag>
 #include <QMouseEvent>
@@ -81,6 +84,7 @@ AppItem::AppItem(const QDBusObjectPath &entry, QWidget *parent)
     connect(m_appPreviewTips, &_PreviewContainer::requestPreviewWindow, this, &AppItem::requestPreviewWindow, Qt::QueuedConnection);
     connect(m_appPreviewTips, &_PreviewContainer::requestCancelPreview, this, &AppItem::requestCancelPreview, Qt::QueuedConnection);
     connect(m_appPreviewTips, &_PreviewContainer::requestHidePreview, this, &AppItem::hidePopup, Qt::QueuedConnection);
+    connect(m_appPreviewTips, &_PreviewContainer::requestCheckWindows, m_itemEntry, &DBusDockEntry::Check);
 
     updateTitle();
     refershIcon();
diff --git a/frame/item/components/_previewcontainer.cpp b/frame/item/components/_previewcontainer.cpp
index 6292beef9..c85b5a67c 100644
--- a/frame/item/components/_previewcontainer.cpp
+++ b/frame/item/components/_previewcontainer.cpp
@@ -133,6 +133,7 @@ void _PreviewContainer::appendSnapWidget(const WId wid)
     connect(snap, &AppSnapshot::clicked, this, &_PreviewContainer::requestCancelPreview, Qt::QueuedConnection);
     connect(snap, &AppSnapshot::clicked, this, &_PreviewContainer::requestHidePreview, Qt::QueuedConnection);
     connect(snap, &AppSnapshot::entered, this, &_PreviewContainer::previewEntered, Qt::QueuedConnection);
+    connect(snap, &AppSnapshot::requestCheckWindow, this, &_PreviewContainer::requestCheckWindows);
 
     m_windowListLayout->addWidget(snap);
 
diff --git a/frame/item/components/_previewcontainer.h b/frame/item/components/_previewcontainer.h
index c35a0297c..99d494dfd 100644
--- a/frame/item/components/_previewcontainer.h
+++ b/frame/item/components/_previewcontainer.h
@@ -29,6 +29,7 @@ signals:
     void requestPreviewWindow(const WId wid) const;
     void requestCancelPreview() const;
     void requestHidePreview() const;
+    void requestCheckWindows() const;
 
 public:
     void setWindowInfos(const WindowDict &infos);
diff --git a/frame/item/components/appsnapshot.cpp b/frame/item/components/appsnapshot.cpp
index 258b3ae39..df14ab0be 100644
--- a/frame/item/components/appsnapshot.cpp
+++ b/frame/item/components/appsnapshot.cpp
@@ -79,9 +79,17 @@ void AppSnapshot::fetchSnapshot()
 
     const auto display = QX11Info::display();
 
-    XWindowAttributes attrs;
-    XGetWindowAttributes(display, m_wid, &attrs);
-    XImage *ximage = XGetImage(display, m_wid, 0, 0, attrs.width, attrs.height, AllPlanes, ZPixmap);
+    Window unused_window;
+    int unused_int;
+    unsigned unused_uint, w, h;
+    XGetGeometry(display, m_wid, &unused_window, &unused_int, &unused_int, &w, &h, &unused_uint, &unused_uint);
+    XImage *ximage = XGetImage(display, m_wid, 0, 0, w, h, AllPlanes, ZPixmap);
+    if (!ximage)
+    {
+        emit requestCheckWindow();
+        return;
+    }
+
     const QImage qimage((const uchar*)(ximage->data), ximage->width, ximage->height, ximage->bytes_per_line, QImage::Format_RGB32);
     Q_ASSERT(!qimage.isNull());
 
diff --git a/frame/item/components/appsnapshot.h b/frame/item/components/appsnapshot.h
index 5fa9aaa5f..14fd73458 100644
--- a/frame/item/components/appsnapshot.h
+++ b/frame/item/components/appsnapshot.h
@@ -25,6 +25,7 @@ public:
 signals:
     void entered(const WId wid) const;
     void clicked(const WId wid) const;
+    void requestCheckWindow() const;
 
 public slots:
     void fetchSnapshot();
diff --git a/frame/item/components/floatingpreview.cpp b/frame/item/components/floatingpreview.cpp
index 7256e747d..c740d4dd7 100644
--- a/frame/item/components/floatingpreview.cpp
+++ b/frame/item/components/floatingpreview.cpp
@@ -48,11 +48,14 @@ void FloatingPreview::paintEvent(QPaintEvent *e)
     if (m_tracked.isNull())
         return;
 
+    const QImage snapshot = m_tracked->snapshot();
+    if (snapshot.isNull())
+        return;
+
     QPainter painter(this);
     painter.setRenderHint(QPainter::Antialiasing);
 
     const QRect r = rect().marginsRemoved(QMargins(8, 8, 8, 8));
-    const QImage snapshot = m_tracked->snapshot();
     const QImage im = snapshot.scaled(r.size(), Qt::KeepAspectRatio, Qt::SmoothTransformation);
     const QRect ir = im.rect();
     const QPoint offset = r.center() - ir.center();