write a regex that matches 4 to 6 characters of base64 string appended by . and then followed by an email

Question

write a regex that matches 4 to 6 characters of base64 string appended by . and then followed by an email with an alphanumeric username component with email domain ending with .in .co .uk

Answer 1

Read this and try yourself:
https://www.sololearn.com/learn/9704/?ref=app