diff --git a/gtk2_ardour/editor_drag.cc b/gtk2_ardour/editor_drag.cc
index 6414c7cf5d..37f71c6026 100644
--- a/gtk2_ardour/editor_drag.cc
+++ b/gtk2_ardour/editor_drag.cc
@@ -365,6 +365,8 @@ RegionDrag::RegionDrag (Editor* e, ArdourCanvas::Item* i, RegionView* p, list<Re
 			}
 		}
 	}
+
+	assert (!v.empty ());
 	
 	for (list<RegionView*>::const_iterator i = v.begin(); i != v.end(); ++i) {
 		_views.push_back (DraggingView (*i, this));
@@ -759,6 +761,8 @@ RegionMoveDrag::finished (GdkEvent *, bool movement_occurred)
 		_x_constrained = !_x_constrained;
 	}
 
+	assert (!_views.empty ());
+
 	bool const changed_position = (_last_frame_position != _primary->region()->position());
 	bool const changed_tracks = (_time_axis_views[_views.front().time_axis_view] != &_views.front().view->get_time_axis_view());
 	framecnt_t const drag_delta = _primary->region()->position() - _last_frame_position;
diff --git a/gtk2_ardour/editor_mouse.cc b/gtk2_ardour/editor_mouse.cc
index 51064f87cc..a3eef66d72 100644
--- a/gtk2_ardour/editor_mouse.cc
+++ b/gtk2_ardour/editor_mouse.cc
@@ -768,6 +768,11 @@ Editor::button_press_handler_1 (ArdourCanvas::Item* item, GdkEvent* event, ItemT
 					*/
 					break;
 				}
+
+				if (internal_editing ()) {
+					/* no region drags in internal edit mode */
+					break;
+				}
 				
 				/* click on a normal region view */
 				if (Keyboard::modifier_state_contains (event->button.state, Keyboard::CopyModifier)) {