Add note about check_page_is_loaded

demo/pages/base/base_page.py

@@ -66,6 +66,13 @@ def check_page_is_loaded(self) -> bool:
         Check that `main` tag is displayed.
 
         """
+        # Be careful with the elements you use to check page load. If you only
+        # use them to check loading, it's better to initiate them directly in
+        # this method. Otherwise, it is better to define them as page
+        # properties or initiate them in the `__init__` method above the
+        # `super().__init__` call. This is necessary because the
+        # `wait_until_loaded` method will be called in `super().__init__`, and
+        # it depends on `check_page_is_loaded`.
         return self.init_element(
             locator=locators.TagNameLocator("main"),
         ).is_displayed