diff --git a/jupyterlab_server/app.py b/jupyterlab_server/app.py
index 28158a37..03c309e1 100644
--- a/jupyterlab_server/app.py
+++ b/jupyterlab_server/app.py
@@ -21,7 +21,7 @@ class LabServerApp(ExtensionAppJinjaMixin, ExtensionApp):
 
     # The name of the extension
     extension_name = "lab"
-
+    
     # Te url that your extension will serve its homepage.
     default_url = '/lab'
 
@@ -66,6 +66,6 @@ def initialize_templates(self):
         )
 
     def initialize_handlers(self):
-        add_handlers(self, self.serverapp.web_app, self.lab_config)
+        add_handlers(self.serverapp.web_app, self.lab_config)
 
 main = launch_new_instance = LabServerApp.launch_instance
diff --git a/jupyterlab_server/handlers.py b/jupyterlab_server/handlers.py
index c4e16469..2ab33305 100644
--- a/jupyterlab_server/handlers.py
+++ b/jupyterlab_server/handlers.py
@@ -54,8 +54,9 @@ def is_url(url):
 class LabHandler(ExtensionHandlerMixin, ExtensionHandlerJinjaMixin, JupyterHandler):
     """Render the JupyterLab View."""
 
+
     def initialize(self, lab_config, **kwargs):
-        super().initialize(kwargs['extension_name'])
+        super().initialize('lab')
         self.lab_config = lab_config
         self.file_loader = FileSystemLoader(lab_config.templates_dir)
 
@@ -209,7 +210,7 @@ def render_template(self, name, **ns):
         return self.render_lab_template(name, **ns)
 
 
-def add_handlers(labserverapp, web_app, config):
+def add_handlers(web_app, config):
     """Add the appropriate handlers to the web app.
     """
     # Normalize directories.
@@ -310,8 +311,7 @@ def add_handlers(labserverapp, web_app, config):
     fallthrough_url = ujoin(base_url, config.app_url, r'.*')
     handlers.append((fallthrough_url, NotFoundHandler, {'lab_config': config}))
 
-#    web_app.add_handlers('.*$', handlers)
-    labserverapp.handlers.extend(handlers)
+    web_app.add_handlers('.*$', handlers)
 
 def _camelCase(base):
     """Convert a string to camelCase.
diff --git a/jupyterlab_server/settings_handler.py b/jupyterlab_server/settings_handler.py
index a7fb95a8..12cbdec5 100644
--- a/jupyterlab_server/settings_handler.py
+++ b/jupyterlab_server/settings_handler.py
@@ -189,7 +189,7 @@ def _path(root_dir, schema_name, make_dirs=False, extension='.json'):
 class SettingsHandler(ExtensionHandlerMixin, ExtensionHandlerJinjaMixin, APIHandler):
 
     def initialize(self, app_settings_dir, schemas_dir, settings_dir, **kwargs):
-        super().initialize(kwargs['extension_name'])
+        super().initialize('lab')
         self.overrides = dict()
         self.schemas_dir = schemas_dir
         self.settings_dir = settings_dir
diff --git a/jupyterlab_server/workspaces_handler.py b/jupyterlab_server/workspaces_handler.py
index 79c2bf4e..6e4fc16f 100644
--- a/jupyterlab_server/workspaces_handler.py
+++ b/jupyterlab_server/workspaces_handler.py
@@ -81,7 +81,7 @@ def slugify(raw, base='', sign=True, max_length=128 - len(WORKSPACE_EXTENSION)):
 class WorkspacesHandler(ExtensionHandlerMixin, ExtensionHandlerJinjaMixin, APIHandler):
 
     def initialize(self, path, workspaces_url=None, **kwargs):
-        super().initialize(kwargs['extension_name'])
+        super().initialize('lab')
         self.workspaces_dir = path
 
     def ensure_directory(self):