Current text field implementation is confusing for many users, especially in desktop and IOS environments. Google realized the problem and they added Text field boxes to the specification in April.
https://material.io/guidelines/components/text-fields.html#text-fields-text-field-boxes
Is there any plan to implement it?
Yes. It was in the April 2017 md spec update and will be implemented.
Most helpful comment
Yes. It was in the April 2017 md spec update and will be implemented.