Just yesterday, I encountered another Web site that told me my up-to-date Firefox ESR was somehow too old, and it showed 3 big icons for their "supported" browsers (Chrome, Safari, and MS Edge).<p>(It was one of those staid non-tech corporate sites that wasn't doing anything beyond forms and a bit of JS, which they could've done 15+ years ago.)<p>Please don't do these "supported browser" games. Instead, use appropriate Web standards that are supported broadly.