Just after the latest update I am getting an fatal error as well:
Fatal error: Uncaught Error: Using $this when not in object context in /www/…/wp-content/plugins/kadence-woocommerce-email-designer/kadence-woocommerce-email-designer.php:348 Stack trace: #0 /www/…/wp-content/plugins/kadence-woocommerce-email-designer/templates/woo/emails/email-header.php(38): Kadence_Woomail_Designer::filter_subtitle(‘Deine Zahlung i…’, Object(WC_Email_Customer_Processing_Order)) #1 /www/…/wp-content/plugins/woocommerce/includes/wc-core-functions.php(211): include(‘/www/htdocs/w01…’) #2 /www/…/wp-content/plugins/kadence-woocommerce-email-designer/kadence-woocommerce-email-designer.php(534): wc_get_template(’emails/email-he…’, Array) #3 /www/…/wp-includes/class-wp-hook.php(286): Kadence_Woomail_Designer->add_email_header(‘Danke f\xC3\xBCr dein…’, Object(WC_Email_Customer_Processing_Order)) #4 /www/…/wp-includes/class-wp-hook.php(310): WP_Hook->apply_filters(NULL in /www/…/wp-content/plugins/kadence-woocommerce-email-designer/kadence-woocommerce-email-designer.php on line 348