diff --git a/addons/web/static/src/js/corelib.js b/addons/web/static/src/js/corelib.js
index 93796ab4282..a7ef3eb9b23 100644
--- a/addons/web/static/src/js/corelib.js
+++ b/addons/web/static/src/js/corelib.js
@@ -1347,6 +1347,9 @@ instance.web.JsonRPC = instance.web.CallbackEnabled.extend({
     },
     on_rpc_error: function(error) {
     },
+    get_url: function (file) {
+        return this.prefix + file;
+    },
 });
 
 }
diff --git a/addons/web/static/src/js/coresetup.js b/addons/web/static/src/js/coresetup.js
index 5a8a2b50722..37e80e44d35 100644
--- a/addons/web/static/src/js/coresetup.js
+++ b/addons/web/static/src/js/coresetup.js
@@ -284,9 +284,6 @@ instance.web.Session = instance.web.JsonRPC.extend( /** @lends instance.web.Sess
             }
         }
     },
-    get_url: function (file) {
-        return this.prefix + file;
-    },
     /**
      * Cooperative file download implementation, for ajaxy APIs.
      *