it compiles, now we get "exc during Lwt.async: Not_found"

.config/init.ml

@@ -9,10 +9,15 @@ let by_id s = Dom_html.getElementById s
 let by_id_coerce s f =
   Js.Opt.get
     (f (Dom_html.getElementById s))
-    (fun () -> raise Not_found)
+    (fun () ->
+      Firebug.console##log (F.str "by_id_coerce Not_found");
+      raise Not_found)
 
 let do_by_id s f =
-  try f (Dom_html.getElementById s) with Not_found -> ()
+  try f (Dom_html.getElementById s)
+  with Not_found ->
+    Firebug.console##log (F.str "do_by_id Not_found");
+    ()
 
 let resize ~container ~textbox () =
   Lwt.pause () >>= fun () ->