**Context:** - Playwright Version: [Version 1.29] - Operating System: [Windows, Mac] - Python version: [3.10] - Browser: [Chromium,] **Code Snippet** ``` def test_mock_tags(page): def handle_route(route: Route): response = route.fetch() json = response.json() json["tags"] = ["implementations", "deserunt"] route.fulfill(json=json, response=response) page.route("**/api/tags", handle_route) page.goto('https://demo.realworld.io/') ``` **Describe the bug** There is no mocking of json data.