An important component of successful web design that is often overlooked by websites' owners is the need for the website to perform equally well across not only all kinds of web browsers but also any of the devices and operating systems that could be running them. It is easy for someone who is relatively new to the responsibilities of a webmaster to fall into the trap of assuming that a design that works in Firefox on a PC running Windows 10 will work as flawlessly in all other modern browsers and devices. This would be true to some extent if one is only attempting to present a website that only works across mainstream browsers routinely updated for Windows 10; one can reasonably expect a design created in Firefox on a desktop PC to work in the desktop versions of browsers like Chrome and Opera.
However, what is arguably the premier web browser for mobile devices and Mac computers is Safari, and there is a considerable likelihood that a Safari browser on a Mac will fail to run certain functions that had only been created with Windows 10 browsers in mind. While Safari had existed as a Windows browser for a time, active development on that version had ceased as of 2012, so it cannot be used as an accurate representation of Safari's performance on other operating systems by any measure.
Fortunately, any web designer working on any platform can easily simulate their current designs' performance on any conceivable operating system and web browser without having to invest in extra hardware. It is technically possible to download programs that emulate these environments within the confines of one's own computer. By getting an account on BrowserStack.com, on the other hand, the user can essentially run their current project through a set of connections linking to physical machines actively running web browsers in real time so that those machines can attempt to load and display the same websites on their end. The user can observe any performance discrepancies between the different platforms and attempt to compensate for them by changing the syntax. For more information click here https://www.reddit.com/r/web_design/comments/d446aa/my_website_is_not_displaying_in_safari_properly/.