fixed some bad behaviors around thumbnail views and document persistence

src/board/UBBoardController.cpp

@@ -1539,10 +1539,10 @@ void UBBoardController::setActiveDocumentScene(UBDocumentProxy* pDocumentProxy,
         mActiveScene = targetScene;
         mActiveSceneIndex = index;
 
-        persistCurrentScene();
-
         setDocument(pDocumentProxy, forceReload);
 
+        persistCurrentScene();
+
         updateSystemScaleFactor();
 
         mControlView->setScene(mActiveScene);

src/gui/UBBoardThumbnailsView.cpp

@@ -190,7 +190,10 @@ void UBBoardThumbnailsView::mousePressEvent(QMouseEvent *event)
     UBDraggableThumbnailView* item = dynamic_cast<UBDraggableThumbnailView*>(itemAt(event->pos()));
 
     if (item)
+    {
+        UBApplication::boardController->persistCurrentScene();
         UBApplication::boardController->setActiveDocumentScene(item->sceneIndex());
+    }
 
     QGraphicsView::mousePressEvent(event);
 }
@@ -202,7 +205,9 @@ void UBBoardThumbnailsView::mouseMoveEvent(QMouseEvent *event)
 
 void UBBoardThumbnailsView::longPressTimeout()
 {
+    if (QApplication::mouseButtons() != Qt::NoButton)
         emit mousePressAndHoldEventRequired(mLastPressedMousePos);
+
     mLongPressTimer.stop();
 }