The CSS property definition syntax has the handy <'property-name'> notation, which imports the entire value space of that property (aside from the CSS-wide keywords).

It's super useful, except a large number of places where we would use it (and did in CSS2) are places where we've listified the property value. This results in a lot of custom non-terminal grammar productions which are simply the entire value space of the property except without the listification, e.g. in css-backgrounds and css-animations.

I suggest we define <'property-name'> to just drop top-level listification. This would allow us to clean up our grammar productions, getting rid of these routine non-terminals and inlining a large number of simple productions into the property definition tables where they are easier to see and index.