Set full screen differently, so it always works

wuttapos/app.py

@@ -162,8 +162,6 @@ def main(page: ft.Page):
         threading.excepthook = thread_exc_hook
 
     page.title = f"WuttaPOS v{wuttapos.__version__}"
-    page.window_full_screen = True
-    # page.vertical_alignment = ft.MainAxisAlignment.CENTER
 
     # global defaults for button/text styles etc.
     page.data = {
@@ -221,6 +219,11 @@ def main(page: ft.Page):
         elif page.route == '/login':
             page.views.append(LoginView(config, '/login'))
 
+        # nb. setting this "last minute" on page change seems to be
+        # more reliable, otherwise the app doesn't always startup in
+        # full screen for some reason
+        page.window_full_screen = True
+
         page.update()
 
     # TODO: this was in example docs but not sure what it's for?