Downbutnotout
Masks are not mandatory, but face coverings are. We are obliged to wear a face covering in shops, indoor areas and on public transport. Its okay to wear a visor or any other reusable face covering. I prefer a visor as this is comfortable, easy to use and hygienic. They can be sanitized after each time you use them.
A visor will not protect you from what is now known to be an airborne virus, unfortunately, , Downbutnotout, no matter how comfortable and convenient.