This is a simple fix although it will help your customers for smooth password reset process. The issue on 6.x.x versions was that newly generated password has a trailing blank space character which result in mismatch (technically) in the password when user copy / paste from their email. Following fix will remove that blank character from new password email.
Find code $plain = $password;That’s it simple fix but save all that customers getting annoyed and abandon shopping 🙂