Custom pop-up for entering a date

Description

Hi, I have a board and I would like to find a way of prompting a pop-up on a status change for the user to enter a date which is then populated into a field in the same board.

What are you trying to achieve

(The actual case is when a project is flagged as “Completed” then I want the user to have to enter the go live date to drive statistics on delivery by a target date).