WSOD when importing sub-contact types
On CiviCRM 5.6.1 when trying to import a, in my case, an organizational sub-contact type, the import fails with a WSOD after mapping fields on step 2.
Here is the error:
[13-Nov-2018 08:09:56 America/New_York] PHP Fatal error: Uncaught Error: [] operator not supported for strings in /home/lporg/www/www/wp-content/plugins/civicrm/civicrm/CRM/Contact/Import/Parser.php:562 Stack trace: #0 /.../.../.../www/wp-content/plugins/civicrm/civicrm/CRM/Contact/Import/Parser/Contact.p hp(417): CRM_Contact_Import_Parser->getActiveFieldParams() #1 (closed) /.../.../.../www/wp-content/plugins/civicrm/civicrm/CRM/Contact/Import/Parser/Contact.p hp(286): CRM_Contact_Import_Parser_Contact->summary(Array) #2 (closed) /.../.../.../www/wp-content/plugins/civicrm/civicrm/CRM/Contact/Import/Parser.php (199): CRM_Contact_Import_Parser_Contact->preview(Array) #3 (closed) /.../.../.../www/wp-content/plugins/civicrm/civicrm/CRM/Contact/Import/Form/MapField.ph p(968): CRM_Contact_Import_Parser->run('civicrm_import_...', Array, 2, 4, '_id', '_status', '4', NULL, NULL, false, 30, 'Local_Affiliate', '11') #4 /.../.../.../www/wp-content/plugins/civicrm/civicrm/CRM/Contact/Import/Form/MapField.ph p(668): CRM_Contact_Import_Form_MapField->submit(Array, Array) #5 /.../.../.../www/ in /.../.../.../www/wp-content/plugins/civicrm/civicrm/CRM/Contact/Import/Parser.php on line 562