2 files changed, 27 insertions, 15 deletions

diff --git a/vcl/inc/qt5/QtTransferable.hxx b/vcl/inc/qt5/QtTransferable.hxx
index 11d673b98a12..38cb4d92005b 100644
--- a/vcl/inc/qt5/QtTransferable.hxx
+++ b/vcl/inc/qt5/QtTransferable.hxx
@@ -36,6 +36,14 @@ class QtTransferable : public cppu::WeakImplHelper<css::datatransfer::XTransfera
     const QMimeData* m_pMimeData;
     bool m_bProvideUTF16FromOtherEncoding;
 
+protected:
+    /** Sets new mime data.
+     *  Since data flavors supported by this class depend on the mime data,
+     *  results from previous calls to the public methods of this
+     *  class are no longer valid after setting new mime data using this method.
+     */
+    void setMimeData(const QMimeData* pMimeData) { m_pMimeData = pMimeData; }
+
 public:
     QtTransferable(const QMimeData* pMimeData);
     const QMimeData* mimeData() const { return m_pMimeData; }
@@ -52,17 +60,17 @@ public:
  * the QClipboard's object thread, which is the QApplication's thread, so all of
  * the access has to go through RunInMainThread().
  *
- * If we detect a QMimeData change, we simply drop reporting any content. In theory
- * we can recover in the case where there hadn't been any calls of the XTransferable
- * interface, but currently we don't. But we ensure to never report mixed content,
- * so we'll just cease operation on QMimeData change.
+ * If we detect a QMimeData change, the mime data is updated with the new one from
+ * the system clipboard. Note however that this means that results of any previous
+ * calls of the XTransferable interface will be out of sync with the newly set mime
+ * data, so this scenario should generally be avoided.
  **/
 class QtClipboardTransferable final : public QtTransferable
 {
     // to detect in-flight QMimeData changes
     const QClipboard::Mode m_aMode;
 
-    bool hasInFlightChanged() const;
+    void ensureConsistencyWithSystemClipboard();
 
 public:
     explicit QtClipboardTransferable(const QClipboard::Mode aMode, const QMimeData* pMimeData);
diff --git a/vcl/qt5/QtTransferable.cxx b/vcl/qt5/QtTransferable.cxx
index 675e5ef75cdc..41c2c58392ef 100644
--- a/vcl/qt5/QtTransferable.cxx
+++ b/vcl/qt5/QtTransferable.cxx
@@ -164,11 +164,15 @@ QtClipboardTransferable::QtClipboardTransferable(const QClipboard::Mode aMode,
 {
 }
 
-bool QtClipboardTransferable::hasInFlightChanged() const
+void QtClipboardTransferable::ensureConsistencyWithSystemClipboard()
 {
-    const bool bChanged(mimeData() != QApplication::clipboard()->mimeData(m_aMode));
-    SAL_WARN_IF(bChanged, "vcl.qt", "In flight clipboard change detected - broken clipboard read!");
-    return bChanged;
+    const QMimeData* pCurrentClipboardData = QApplication::clipboard()->mimeData(m_aMode);
+    if (mimeData() != pCurrentClipboardData)
+    {
+        SAL_WARN("vcl.qt", "In flight clipboard change detected - updating mime data with current "
+                           "clipboard contents.");
+        setMimeData(pCurrentClipboardData);
+    }
 }
 
 css::uno::Any SAL_CALL
@@ -178,8 +182,8 @@ QtClipboardTransferable::getTransferData(const css::datatransfer::DataFlavor& rF
     auto* pSalInst(GetQtInstance());
     SolarMutexGuard g;
     pSalInst->RunInMainThread([&, this]() {
-        if (!hasInFlightChanged())
-            aAny = QtTransferable::getTransferData(rFlavor);
+        ensureConsistencyWithSystemClipboard();
+        aAny = QtTransferable::getTransferData(rFlavor);
     });
     return aAny;
 }
@@ -191,8 +195,8 @@ css::uno::Sequence<css::datatransfer::DataFlavor>
     auto* pSalInst(GetQtInstance());
     SolarMutexGuard g;
     pSalInst->RunInMainThread([&, this]() {
-        if (!hasInFlightChanged())
-            aSeq = QtTransferable::getTransferDataFlavors();
+        ensureConsistencyWithSystemClipboard();
+        aSeq = QtTransferable::getTransferDataFlavors();
     });
     return aSeq;
 }
@@ -204,8 +208,8 @@ QtClipboardTransferable::isDataFlavorSupported(const css::datatransfer::DataFlav
     auto* pSalInst(GetQtInstance());
     SolarMutexGuard g;
     pSalInst->RunInMainThread([&, this]() {
-        if (!hasInFlightChanged())
-            bIsSupported = QtTransferable::isDataFlavorSupported(rFlavor);
+        ensureConsistencyWithSystemClipboard();
+        bIsSupported = QtTransferable::isDataFlavorSupported(rFlavor);
     });
     return bIsSupported;
 }