diff --git a/gtk2_ardour/editor.cc b/gtk2_ardour/editor.cc
index d173f5153f..de92b24e98 100644
--- a/gtk2_ardour/editor.cc
+++ b/gtk2_ardour/editor.cc
@@ -7032,7 +7032,7 @@ Editor::default_time_domain () const
 void
 Editor::start_track_drag (TimeAxisView& tav, int y, Gtk::Widget& w)
 {
-	track_drag = new TrackDrag (dynamic_cast<RouteTimeAxisView*> (&tav));
+	track_drag = new TrackDrag (dynamic_cast<RouteTimeAxisView*> (&tav), *_session);
 	DEBUG_TRACE (DEBUG::TrackDrag, string_compose ("start track drag with %1\n", track_drag));
 
 	track_drag->drag_cursor = _cursors->move->gobj();
diff --git a/gtk2_ardour/editor.h b/gtk2_ardour/editor.h
index 30b1c62270..ace3782ccd 100644
--- a/gtk2_ardour/editor.h
+++ b/gtk2_ardour/editor.h
@@ -2627,7 +2627,7 @@ private:
 		int                direction;
 		bool               first_move;
 
-		TrackDrag (RouteTimeAxisView* rtav)
+		TrackDrag (RouteTimeAxisView* rtav, ARDOUR::Session& s)
 			: track (rtav)
 			, drag_cursor (nullptr)
 			, predrag_cursor (nullptr)