Possible to copy & paste password into Mac Users field for adding new accounts?

I need to create a new account to my Mac computer. The current account I am logged onto the Mac with doesn't have administrator rights.

The password for the local administrator account (which I need to type in when creating a new user account on this Mac) could be any of 20 different password combinations. All of these passwords are very complex.

On other Macs I have been able to put the password into the Mac clipboard and then paste the password into this field.

However, on this particular Mac when I try to paste the password into this field the password isn't pasted.

What do I need to do on this Mac to enable me to be able to copy & paste the passwords into this field?