Testing a browser extension is more than checking a web page. You may need to prepare storage, open an extension popup, options page, or side panel, trigger browser events, and check data migration between extension versions. Playwright's official extensions guide shows how to launch a browser with an extension, wait for its service worker, and find its ID. That gives a good starting point, but the extension-specific parts of the tests still need fixtures and helpers. In this post, I wan...