autofocus attribute must not be specified in <input> element whose type attribute is in the Hidden state

[mtrootyy]

https://html.spec.whatwg.org/multipage/input.html#hidden-state-(type=hidden)

Bookkeeping details

• The autocomplete content attribute applies to this element.
• The value IDL attribute applies to this element and is in mode default.
• The following content attributes must not be specified and do not apply to the element: accept, alt, ......
• The following IDL attributes and methods do not apply to the element: checked, files, ......
• The input and change events do not apply.

　↓

The above should be fixed following:

Bookkeeping details

• The autocomplete content attribute applies to this element.
• The element's autofocus attribute must not be specified.
• The value IDL attribute applies to this element and is in mode default.
• The following content attributes must not be specified and do not apply to the element: accept, alt, ......
• The following IDL attributes and methods do not apply to the element: checked, files, ......
• The input and change events do not apply.

　
Because it is impossible to focus on input element whose type attribute is in the Hidden state.

[annevk]

Does it apply in user agents? If not, shouldn't we add it to the list of content attributes that must not be specified and do not apply?

[domenic]

It's unclear why we would add this, to me. An input type=hidden could become type=text at a later time, in which case specifying autofocus could be useful.

In other words, I don't think we currently try to prohibit specifying autofocus on hidden elements in general (e.g. <input type=text hidden>), or disabled elements, or similar. I wouldn't want to special case input type=hidden.

[annevk]

But autofocus only takes effect during insertion, not when a type attribute of an input element changes. There might well be a larger issue though.

[domenic]

Given #4830, I think it's best to close this.