PHP Fatal error: Call to undefined method wpdb::prepared()

Overview of the issue

This is for websites using the ICanLocalize translation service.

When clicking the “Get completed translations” button from either the Dashboard or Translation Management interfaces, the ajax loading icon won’t stop spinning and an error will get generated:

PHP Fatal error: Call to undefined method wpdb::prepared() in /…/wp-content/plugins/sitepress-multilingual-cms/inc/translation-management/pro-translation.class.php on line 1757

The “Get completed translations” button may not work correctly.

Workaround

Meanwhile you can fix this issue by editing sitepress-multilingual-cms/inc/translation-management/pro-translation.class.php at line 1757 and fixing $wpdb->prepared with $wpdb->prepare.