Website sites will look different in different browsers. That’s because browsers understand code slightly differently. Its important to understand that one site will look different across browsers and even versions of browsers.
Browser testing no longer means attempting to make a website or app look exactly the same in all browsers of different capabilities or on devices with different size screens. It does mean ensuring that a person’s experience of a design should be appropriate to the capabilities of a browser or device.
Since browsers are constantly updating and new versions are being released on a regular basis, keeping track of any changes that might impact how sites work is important. It is essential to continue to test across a wide variety of browsers/devices in order to accommodate a broader audience.
Sites that were built a few years ago might be due for a refresh. Responsive design is really the base standard going forward. Your site should look GOOD in all browsers but that doesn’t mean it has to look exactly the same.