Atlas › 13 Browser Automation with Playwright › Contexts, Waiting, and Assertions☰ Read as one page
Contexts, Waiting, and Assertions
6.1OverviewThree concepts form the core of Playwright's reliability advantage over earlier tools: browser contexts for isolation, auto-waiting to…6.2Browser ContextsA browser context is a lightweight, isolated browser session — like an incognito window. Each context has its own cookies, localStorage…6.3Auto-WaitingIn Selenium, the #1 source of test flakiness is timing: the test tries to interact with an element before it is ready. Playwright…6.4Web-First AssertionsPlaywright's expect() assertions are "web-first" — they retry until the condition is met or the timeout expires. This is fundamentally…6.5Putting It All TogetherNo explicit waits. No sleep statements. No flaky timing issues. The auto-waiting and web-first assertions handle all synchronization.6.6Key Takeaways- Browser contexts provide lightweight, isolated sessions — no state leaks between tests - Auto-waiting checks actionability (visible…