Since Administrate was released, browser support for native fields around date/time/datetime picking has improved substantially. Now, every major browser has adequate support for native pickers.
For those who need to support older browsers, we'd recommend using a polyfill such as: https://github.com/jonstipe/datetime-local-polyfill
This commit should maintain like-for-like compatability, including
allowing filling out seconds by setting the step attribute.
https://caniuse.com/input-datetime https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input/datetime-local https://stackoverflow.com/questions/20111413/html5-datetime-local-control-how-to-hide-seconds