Case-Insensitive Duplicate Emails

Emails differ only by letter case and surrounding spaces. Return each normalised email (lower case, trimmed) and how many rows map to it, only when more than one does. Order by email.

Table schema

Signups(id INT PRIMARY KEY, email VARCHAR(30))

Sample data

id | email
1 | Ann@X.com
2 |  ann@x.com
3 | bob@x.com
4 | BOB@x.com 
5 | cy@x.com