Cross-Browser Testing
Cross-browser testing verifies that a web application renders and functions correctly across different browsers — Chrome, Firefox, Safari, Edge — and their various versions. Browsers implement web standards with small but real differences, so code that works perfectly in one can render or behave differently in another.
Modern cross-browser testing is far less painful than it used to be, thanks to standards convergence and evergreen (auto-updating) browsers, but real gaps remain — CSS rendering quirks, JavaScript API support differences, and Safari's historically slower adoption of some web platform features.
Playwright and Selenium both support running the same automated test suite against multiple browser engines with minimal script changes, which is why most teams automate this rather than manually re-testing every feature in every browser by hand.
