> - The built-in rule for [hidden] { display: none; } is often of no help as another css class may set display to something else, so from the developer's perspe

> - The built-in rule for [hidden] { display: none; } is often of no help as another css class may set display to something else, so from the developer's perspective the "hidden" attribute seems to be broken. [hidden] { display: none !imporant; } is one of the few examples where I think `!important` is OK.