CRED Commerce user registration fails throwing a warning

Symptoms

User registration using a form created with CRED, Commerce and WooCommerce fails on submission, throwing the following warning:

Warning: trim() expects parameter 1 to be a string, 
array given ../wp-includes/class-wp-user.php on line 206

Workaround

This issue will be fixed in the next release of Toolset CRED.

In the meantime, you can download this file, extract it and replace the

UserForms.php file in /plugins/cred-frontend-editor/library/toolset/cred/embedded/models/ folder.

Please remember to keep a backup of your site and database before doing this.