diff --git a/libs/canvas/widget.cc b/libs/canvas/widget.cc
index 25541c1660..a1344a5f87 100644
--- a/libs/canvas/widget.cc
+++ b/libs/canvas/widget.cc
@@ -91,11 +91,9 @@ Widget::compute_bounding_box () const
 {
 	std::cerr << "cbbox for widget\n";
 
-	GtkRequisition req = { 0, 0 };
+	GtkRequisition req = _widget.size_request ();
 	Gtk::Allocation alloc;
 
-	_widget.size_request (req);
-
 	std::cerr << "widget wants " << req.width << " x " << req.height << "\n";
 
 	_bounding_box = Rect (0, 0, req.width, req.height);