What about one common prefix in addition to vendor prefixes? Then you could write "-x-border-radius: 2px" in the majority of times where the property was compa

What about one common prefix in addition to vendor prefixes? Then you could write "-x-border-radius: 2px" in the majority of times where the property was compatible, but you'd still be able to write "-webkit-border-radius: 2px 4px; -moz-border-radius: 4px 2px" where it's implemented differently.