This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.
<input type="datetime"> was a control for entering a date and time (hour, minute, second, and fraction of a second) as well as a timezone. This feature has been removed from WHATWG HTML, and is no longer supported in browsers.
Instead, browsers are implementing (and developers are encouraged to use)