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<?php $order = []; echo var_export(isset($order['billing_address']['form_fields'][1]));
Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
false
preferences:
57.97 ms | 1230 KiB | 4 Q