State of the dependencies of the web client

[ced (Cédric Krier)]

@ced

This is not widely supported enough: Date and time input types | Can I use... Support tables for HTML5, CSS3, etc
Also I have serious doubt about correctness of such input because JavaScript has no real date object.

Maybe we could use the date, time and datetime-local as long as we have fallback support (without popup) for browsers that does not support them (so they behave like text input).