Add pop up message for National Identifier country field for the countries that are not applicable.

Summary:

We have disenabled the Common Lookup tags of National Id Type for three countries in Dev1. Now the candidates will be able to see the country names under National Identifier but they won’t be able to fill in National ID Type and Number. And further so they won’t be able to save the National Identifier data under these 3 countries. Can we create a text or message popping up and informing the candidate that these three countries cannot be chosen, otherwise they will think that there is a technical issue. Is it possible to have a pop up message?