<form>新属性：
- autocomplete
- 规定 form 或 input 域应该拥有自动完成功能。https://www.runoob.com/try/try.php?filename=tryhtml5_input_autocomplete
- novalidate
<input>新属性：
- autocomplete
- autofocus
- form
- formaction
- formenctype
- formmethod
- formnovalidate
- formtarget
- height 与 width
- list
- min 与 max
- multiple
- pattern (regexp)
- placeholder
- required
- step
来源：https://www.cnblogs.com/1016391912pm/p/12602754.html