diff --git a/src/briar/gtk/application.py b/src/briar/gtk/application.py
index 95e57e4074434d0a943f9406664b2b65db04f132..6aa73db5af02d49abd4013a07a15efe6243692c0 100644
--- a/src/briar/gtk/application.py
+++ b/src/briar/gtk/application.py
@@ -11,7 +11,7 @@ from gi.repository import Gdk, Gio, GLib, Gtk
 from briar.api.api import Api
 
 from briar.gtk.define import APPLICATION_ID, APPLICATION_NAME
-from briar.gtk.define import APPLICATION_STYLING, BRIAR_HEADLESS_JAR
+from briar.gtk.define import APPLICATION_STYLING_PATH, BRIAR_HEADLESS_JAR
 from briar.gtk.window import Window
 
 
@@ -24,7 +24,7 @@ class Application(Gtk.Application):
     # pylint: disable=arguments-differ
     def do_startup(self):
         Gtk.Application.do_startup(self)
-        Application._setup_styling(APPLICATION_STYLING)
+        Application._setup_styling(APPLICATION_STYLING_PATH)
         self._setup_api()
 
     # pylint: disable=arguments-differ
@@ -34,7 +34,7 @@ class Application(Gtk.Application):
     # pylint: disable=arguments-differ
     def quit(self):
         self.api.stop()
-        self.window.hide()
+        self._window.hide()
         Gio.Application.quit(self)
 
     @staticmethod
@@ -43,8 +43,8 @@ class Application(Gtk.Application):
         GLib.set_prgname(name)
 
     @staticmethod
-    def _setup_styling(styling):
-        css_provider_file = Gio.File.new_for_uri(styling)
+    def _setup_styling(styling_path):
+        css_provider_file = Gio.File.new_for_uri(styling_path)
         css_provider = Gtk.CssProvider()
         css_provider.load_from_file(css_provider_file)
 
@@ -58,7 +58,7 @@ class Application(Gtk.Application):
 
     # pylint: disable=access-member-before-definition
     def _setup_window(self):
-        if not hasattr(self, "window") or self.window is None:
-            self.window = Window()
-            self.window.show()
-        self.window.present()
+        if not hasattr(self, "_window") or self._window is None:
+            self._window = Window()
+            self._window.show()
+        self._window.present()
diff --git a/src/briar/gtk/define.py b/src/briar/gtk/define.py
index 59051148bc288a755d11e9dae7421ec1255f32ad..4e893dad467906291ef35f62d9e32ebfbe2d077f 100644
--- a/src/briar/gtk/define.py
+++ b/src/briar/gtk/define.py
@@ -10,7 +10,7 @@ from gi.repository import Gio
 
 APPLICATION_ID = "app.briar.gtk"
 APPLICATION_NAME = "Briar"
-APPLICATION_STYLING = "resource:///app/briar/gtk/ui/application.css"
+APPLICATION_STYLING_PATH = "resource:///app/briar/gtk/ui/application.css"
 BRIAR_HEADLESS_JAR = "/app/briar/briar-headless.jar"
 
 APP = Gio.Application.get_default
diff --git a/tests/briar/gtk/test_application.py b/tests/briar/gtk/test_application.py
index 5c20aff10dd152be8e4039aa9f0dcb5af1a586a8..f3c375f1287a1a036e0eb57a0f4d8b425b8b3e24 100644
--- a/tests/briar/gtk/test_application.py
+++ b/tests/briar/gtk/test_application.py
@@ -6,7 +6,7 @@ from unittest.mock import Mock
 
 from briar.api.api import Api
 from briar.gtk.application import Application
-from briar.gtk.define import APPLICATION_NAME, APPLICATION_STYLING
+from briar.gtk.define import APPLICATION_NAME, APPLICATION_STYLING_PATH
 from briar.gtk.define import BRIAR_HEADLESS_JAR
 from briar.gtk.window import Window
 
@@ -21,7 +21,7 @@ def test_do_startup(mocker):
     Application().do_startup()
 
     do_startup_mock.assert_called_once()
-    _setup_styling_mock.assert_called_once_with(APPLICATION_STYLING)
+    _setup_styling_mock.assert_called_once_with(APPLICATION_STYLING_PATH)
     _setup_api_mock.assert_called_once()
 
 
@@ -43,7 +43,7 @@ def test_quit(mocker):
 
     application = Application()
     application.api = api_mock
-    application.window = window_mock
+    application._window = window_mock
 
     application.quit()
 
@@ -83,9 +83,9 @@ def test_setup_styling(mocker):
     add_provider_for_screen_mock = mocker.patch(
         "gi.repository.Gtk.StyleContext.add_provider_for_screen")
 
-    Application._setup_styling(APPLICATION_STYLING)
+    Application._setup_styling(APPLICATION_STYLING_PATH)
 
-    new_for_uri_mock.assert_called_with(APPLICATION_STYLING)
+    new_for_uri_mock.assert_called_with(APPLICATION_STYLING_PATH)
     load_from_file_mock.assert_called_once()
     get_default_mock.assert_called_once()
     add_provider_for_screen_mock.assert_called_once()
@@ -118,7 +118,7 @@ def test_setup_window_has_attribute(mocker):
     window_mock = Mock()
 
     application = Application()
-    application.window = window_mock
+    application._window = window_mock
 
     application._setup_window()
 
@@ -132,7 +132,6 @@ def test_setup_window_has_none_attribute(mocker):
     window_present_mock = mocker.patch("briar.gtk.window.Window.present")
 
     application = Application()
-    application.window = None
 
     application._setup_window()