Essential Tools for Testing Cross-Browser Compatibility on Your WordPress Site
If you’re not testing how your site looks and performs on different browsers, you really have no idea whether visitors to your site are viewing it as you intended. Add to that, testing on multiple browsers on different operating systems and different devices is also a must. After all, Google Chrome on OS X isn’t quite like Google Chrome on Windows or Google Chrome on an iPhone 6S.
Source: Essential Tools for Testing Cross-Browser Compatibility on Your WordPress Site