Show product's extra information inline on Order Received page and Email Notification

functions.php

<?php

function woocommerce_order_item_get_formatted_meta_data_callback( $formatted_meta ){

	foreach ( $formatted_meta as $key => $value ) {
		$formatted_meta[$key]->display_value = wp_strip_all_tags( $value->display_value );
	}
	return $formatted_meta;
}
add_filter( "woocommerce_order_item_get_formatted_meta_data", "woocommerce_order_item_get_formatted_meta_data_callback", 10, 1 );

?>