The interface displays 10 "*" for security reasons
The whole point of using "*" when displaying a password field is so nobody can see your password.
If the field shows "***" for a 3-character password, it's possible to break in using a brute-force attack with 1000 attempts. This way, we hide not only the content, but also the length.
It's just common sense security.
If you input a 4-char password, it will be stored correctly.