Hi,
so first of all I want to say that I am aware that is not necessarily a Fluent UI bug. However, I still wanted to create an issue because you can and might want to fix it.

It seems like Safari adds a 2px margin to the left and right of each button. This has some strange effects that are probably not wanted. To see the issue, use Safari and go to https://developer.microsoft.com/en-us/fluentui#/controls/web/button. The layout is slightly off and there are some probably unwanted gaps. Here is one of them:

So please feel free to turn this into a feature request or even leave it up to the Safari team. However, from a developer point of view I'd appreciate it if the framework looks the same in all browsers without additional fixes.

Environment Information

• Browser and OS versions: Safari 15