Fixed a bug related to the scroll slide timer not being correctly

terminated

src/gui/widgets/timeline/timeline-header-container.cpp

@@ -426,6 +426,9 @@ TimelineHeaderContainer::end_drag(bool apply)
   if(layout.is_dragging_track())
     layout.end_dragging_track(apply);
   
+  // End the scroll slide
+  end_scroll_slide();
+    
   // Reset the arrow as a cursor
   REQUIRE(gdkWindow);
   gdkWindow->set_cursor(Gdk::Cursor(Gdk::ARROW));