diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -29,6 +29,7 @@
 target_link_libraries(
     dolphinvcs PUBLIC
     Qt5::Widgets
+    Qt5::Concurrent
 )
 
 set_target_properties(dolphinvcs PROPERTIES
diff --git a/src/kitemviews/kitemlistcontroller.h b/src/kitemviews/kitemlistcontroller.h
--- a/src/kitemviews/kitemlistcontroller.h
+++ b/src/kitemviews/kitemlistcontroller.h
@@ -29,6 +29,7 @@
 
 #include <QObject>
 #include <QPointF>
+#include <QCache>
 class QTimer;
 class KItemModelBase;
 class KItemListKeyboardSearchManager;
@@ -347,6 +348,11 @@
      */
     int m_keyboardAnchorIndex;
     qreal m_keyboardAnchorPos;
+    /**
+     * Stores the expensive to calculate results of the checks if a (long) list of urls
+     * contains a directory url, i.e. trying to paste over itself.
+     */
+    QHash<QUrl, bool> m_dropAccepted;
 };
 
 #endif
diff --git a/src/kitemviews/kitemlistcontroller.cpp b/src/kitemviews/kitemlistcontroller.cpp
--- a/src/kitemviews/kitemlistcontroller.cpp
+++ b/src/kitemviews/kitemlistcontroller.cpp
@@ -58,7 +58,8 @@
     m_autoActivationTimer(nullptr),
     m_oldSelection(),
     m_keyboardAnchorIndex(-1),
-    m_keyboardAnchorPos(0)
+    m_keyboardAnchorPos(0),
+    m_dropAccepted()
 {
     connect(m_keyboardManager, &KItemListKeyboardSearchManager::changeCurrentItem,
             this, &KItemListController::slotChangeCurrentItem);
@@ -849,6 +850,9 @@
 {
     Q_UNUSED(event);
     Q_UNUSED(transform);
+
+    m_dropAccepted.clear();
+
     return false;
 }
 
@@ -875,7 +879,6 @@
         return false;
     }
 
-
     QUrl hoveredDir = m_model->directory();
     KItemListWidget* oldHoveredWidget = hoveredWidget();
 
@@ -929,7 +932,12 @@
         m_view->hideDropIndicator();
     }
 
-    event->setAccepted(!DragAndDropHelper::urlListMatchesUrl(event->mimeData()->urls(), hoveredDir));
+    if (!m_dropAccepted.contains(hoveredDir))
+    {
+        m_dropAccepted.insert(hoveredDir,
+                !DragAndDropHelper::urlListMatchesUrl(event->mimeData()->urls(), hoveredDir));
+    }
+    event->setAccepted(m_dropAccepted[hoveredDir]);
 
     return false;
 }
diff --git a/src/views/draganddrophelper.cpp b/src/views/draganddrophelper.cpp
--- a/src/views/draganddrophelper.cpp
+++ b/src/views/draganddrophelper.cpp
@@ -39,6 +39,10 @@
 
 KIO::DropJob* DragAndDropHelper::dropUrls(const QUrl& destUrl, QDropEvent* event, QWidget* window)
 {
+    // The drop event isn't accpeted. Could for instance be because of dropping on itself.
+    if (!event->isAccepted()) {
+        return nullptr;
+    }
     const QMimeData* mimeData = event->mimeData();
     if (mimeData->hasFormat(QStringLiteral("application/x-kde-ark-dndextract-service")) &&
         mimeData->hasFormat(QStringLiteral("application/x-kde-ark-dndextract-path"))) {