The numbers there are highly arbitrary - some things have large subcategories and so a big final number, while huge features like WebGL have few subcategories a

The numbers there are highly arbitrary - some things have large subcategories and so a big final number, while huge features like WebGL have few subcategories and a small final number. The numbers there are just an arbitrary decision by, AFAICT, one person. Edit: Also, that does not include JS features at all. The modern web isn't just HTML ;)