All websites should be designed for Cross Browser support, if not that is very poor coding, it should work in ALL Browsers. Chrome, Firefox, safari, Internet Explorer. The website should also be checked for responsive = Ipads/Phones/Tablets etc.
An easy way to test cross browser compatability is using Chrome built in tools, this is the first thing a web designer should do = Good practise.
developers.google.com
www.digitalcitizen.life
Also an extension for chrome which is very easy:
An easy way to test cross browser compatability is using Chrome built in tools, this is the first thing a web designer should do = Good practise.
Chrome DevTools | Chrome for Developers
Debug and optimize your web applications with Chrome DevTools.


How to use the mobile browser emulator in Chrome, Firefox, Edge, Opera
Do you need to access a smartphone browser emulator on your PC to test the mobile version of a website you are interested in? Maybe you are a web developer, or you want to become one, and you need to simulate a mobile browser for the project you are working on. Regardless of your reasons, […]

Also an extension for chrome which is very easy: