Problem: I would like to display some content conditionally based on whether or not the User's WooCommerce 'billing_phone' field has a value.

Solution: In the legacy editor, you can use the following syntax to test the value of a User's WooCommerce field:

[wpv-conditional if="( '[wpv-user field="billing_phone"]' eq '' )"]
empty billing phone
[/wpv-conditional]
[wpv-conditional if="( '[wpv-user field="billing_phone"]' ne '' )"]
non-empty billing phone
[/wpv-conditional]