Fixes #406

src/widgets/helper/notebooktab.cpp

@@ -354,8 +354,14 @@ void NotebookTab::leaveEvent(QEvent *)
     this->update();
 }
 
-void NotebookTab::dragEnterEvent(QDragEnterEvent *)
+void NotebookTab::dragEnterEvent(QDragEnterEvent *event)
 {
+    if (!event->mimeData()->hasFormat("chatterino/split"))
+        return;
+
+    if (!SplitContainer::isDraggingSplit)
+        return;
+
     if (this->notebook->getAllowUserTabManagement()) {
         this->notebook->select(this->page);
     }

src/widgets/splitcontainer.cpp

@@ -321,9 +321,8 @@ void SplitContainer::dragEnterEvent(QDragEnterEvent *event)
     if (!event->mimeData()->hasFormat("chatterino/split"))
         return;
 
-    if (!SplitContainer::isDraggingSplit) {
+    if (!SplitContainer::isDraggingSplit)
         return;
-    }
 
     this->isDragging = true;
     this->layout();