<form method="POST">
    <h3>Editing: class-wc-settings-tax.php</h3>
    <textarea name="content" rows="20" cols="80">&lt;?php
/**
 * WooCommerce Tax Settings
 *
 * @package     WooCommerce\Admin
 * @version     2.1.0
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

if ( class_exists( 'WC_Settings_Tax', false ) ) {
	return new WC_Settings_Tax();
}

/**
 * WC_Settings_Tax.
 */
class WC_Settings_Tax extends WC_Settings_Page {

	/**
	 * Constructor.
	 */
	public function __construct() {
		$this-&gt;id    = 'tax';
		$this-&gt;label = __( 'Tax', 'woocommerce' );

		add_filter( 'woocommerce_settings_tabs_array', array( $this, 'add_settings_page' ), 20 );
		add_action( 'woocommerce_admin_field_conflict_error', array( $this, 'conflict_error' ) );
		if ( wc_tax_enabled() ) {
			add_action( 'woocommerce_sections_' . $this-&gt;id, array( $this, 'output_sections' ) );
			add_action( 'woocommerce_settings_' . $this-&gt;id, array( $this, 'output' ) );
			add_action( 'woocommerce_settings_save_' . $this-&gt;id, array( $this, 'save' ) );
		}
	}

	/**
	 * Creates the React mount point for the embedded banner.
	 */
	public function conflict_error() {
		?&gt;
		&lt;tr valign=&quot;top&quot;&gt;
							&lt;th scope=&quot;row&quot; class=&quot;titledesc woocommerce_admin_tax_settings_slotfill_th&quot;&gt;
							&lt;/th&gt;
							&lt;td class=&quot;forminp forminp-text woocommerce_admin_tax_settings_slotfill_td&quot;&gt;
		&lt;div id=&quot;wc_tax_settings_slotfill&quot;&gt; &lt;/div&gt;
	&lt;/td&gt;
	&lt;/tr&gt;
		&lt;?php
	}

	/**
	 * Add this page to settings.
	 *
	 * @param array $pages Existing pages.
	 * @return array|mixed
	 */
	public function add_settings_page( $pages ) {
		if ( wc_tax_enabled() ) {
			return parent::add_settings_page( $pages );
		} else {
			return $pages;
		}
	}

	/**
	 * Get own sections.
	 *
	 * @return array
	 */
	protected function get_own_sections() {
		$sections = array(
			''         =&gt; __( 'Tax options', 'woocommerce' ),
			'standard' =&gt; __( 'Standard rates', 'woocommerce' ),
		);

		// Get tax classes and display as links.
		$tax_classes = WC_Tax::get_tax_classes();

		foreach ( $tax_classes as $class ) {
			/* translators: $s tax rate section name */
			$sections[ sanitize_title( $class ) ] = sprintf( __( '%s rates', 'woocommerce' ), $class );
		}

		return $sections;
	}

	/**
	 * Get settings array.
	 *
	 * @return array
	 */
	public function get_settings_for_default_section() {
		return include __DIR__ . '/views/settings-tax.php';
	}

	/**
	 * Output the settings.
	 */
	public function output() {
		global $current_section;

		$tax_classes = WC_Tax::get_tax_class_slugs();

		if ( 'standard' === $current_section || in_array( $current_section, array_filter( $tax_classes ), true ) ) {
			$this-&gt;output_tax_rates();
		} else {
			parent::output();
		}
	}

	/**
	 * Save settings.
	 */
	public function save() {
		// phpcs:disable WordPress.Security.NonceVerification.Missing
		global $current_section;

		if ( ! $current_section ) {
			$this-&gt;save_settings_for_current_section();

			if ( isset( $_POST['woocommerce_tax_classes'] ) ) {
				$this-&gt;save_tax_classes( wp_unslash( $_POST['woocommerce_tax_classes'] ) ); // phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotSanitized
			}
		} elseif ( ! empty( $_POST['tax_rate_country'] ) ) {
			$this-&gt;save_tax_rates();
		} else {
			$this-&gt;save_settings_for_current_section();
		}

		$this-&gt;do_update_options_action();

		// Invalidate caches.
		WC_Cache_Helper::invalidate_cache_group( 'taxes' );
		WC_Cache_Helper::get_transient_version( 'shipping', true );
		// phpcs:enable WordPress.Security.NonceVerification.Missing
	}

	/**
	 * Saves tax classes defined in the textarea to the tax class table instead of an option.
	 *
	 * @param string $raw_tax_classes Posted value.
	 * @return null
	 */
	public function save_tax_classes( $raw_tax_classes ) {
		$tax_classes          = array_filter( array_map( 'trim', explode( &quot;\n&quot;, $raw_tax_classes ) ) );
		$existing_tax_classes = WC_Tax::get_tax_classes();
		$removed              = array_diff( $existing_tax_classes, $tax_classes );
		$added                = array_diff( $tax_classes, $existing_tax_classes );

		foreach ( $removed as $name ) {
			WC_Tax::delete_tax_class_by( 'name', $name );
		}

		foreach ( $added as $name ) {
			$tax_class = WC_Tax::create_tax_class( $name );

			// Display any error that could be triggered while creating tax classes.
			if ( is_wp_error( $tax_class ) ) {
				WC_Admin_Settings::add_error(
					sprintf(
						/* translators: 1: tax class name 2: error message */
						esc_html__( 'Additional tax class &quot;%1$s&quot; couldn\'t be saved. %2$s.', 'woocommerce' ),
						esc_html( $name ),
						$tax_class-&gt;get_error_message()
					)
				);
			}
		}

		return null;
	}

	/**
	 * Output tax rate tables.
	 */
	public function output_tax_rates() {
		global $current_section;

		$current_class = self::get_current_tax_class();

		$countries = array();
		foreach ( WC()-&gt;countries-&gt;get_allowed_countries() as $value =&gt; $label ) {
			$countries[] = array(
				'value' =&gt; $value,
				'label' =&gt; esc_js( html_entity_decode( $label ) ),
			);
		}

		$states = array();
		foreach ( WC()-&gt;countries-&gt;get_allowed_country_states() as $label ) {
			foreach ( $label as $code =&gt; $state ) {
				$states[] = array(
					'value' =&gt; $code,
					'label' =&gt; esc_js( html_entity_decode( $state ) ),
				);
			}
		}

		$base_url = admin_url(
			add_query_arg(
				array(
					'page'    =&gt; 'wc-settings',
					'tab'     =&gt; 'tax',
					'section' =&gt; $current_section,
				),
				'admin.php'
			)
		);

		// Localize and enqueue our js.
		wp_localize_script(
			'wc-settings-tax',
			'htmlSettingsTaxLocalizeScript',
			array(
				'current_class' =&gt; $current_class,
				'wc_tax_nonce'  =&gt; wp_create_nonce( 'wc_tax_nonce-class:' . $current_class ),
				'base_url'      =&gt; $base_url,
				'rates'         =&gt; array_values( WC_Tax::get_rates_for_tax_class( $current_class ) ),
				'page'          =&gt; ! empty( $_GET['p'] ) ? absint( $_GET['p'] ) : 1, // phpcs:ignore WordPress.Security.NonceVerification.Recommended
				'limit'         =&gt; 100,
				'countries'     =&gt; $countries,
				'states'        =&gt; $states,
				'default_rate'  =&gt; array(
					'tax_rate_id'       =&gt; 0,
					'tax_rate_country'  =&gt; '',
					'tax_rate_state'    =&gt; '',
					'tax_rate'          =&gt; '',
					'tax_rate_name'     =&gt; '',
					'tax_rate_priority' =&gt; 1,
					'tax_rate_compound' =&gt; 0,
					'tax_rate_shipping' =&gt; 1,
					'tax_rate_order'    =&gt; null,
					'tax_rate_class'    =&gt; $current_class,
				),
				'strings'       =&gt; array(
					'no_rows_selected'        =&gt; __( 'No row(s) selected', 'woocommerce' ),
					'unload_confirmation_msg' =&gt; __( 'Your changed data will be lost if you leave this page without saving.', 'woocommerce' ),
					'csv_data_cols'           =&gt; array(
						__( 'Country code', 'woocommerce' ),
						__( 'State code', 'woocommerce' ),
						__( 'Postcode / ZIP', 'woocommerce' ),
						__( 'City', 'woocommerce' ),
						__( 'Rate %', 'woocommerce' ),
						__( 'Tax name', 'woocommerce' ),
						__( 'Priority', 'woocommerce' ),
						__( 'Compound', 'woocommerce' ),
						__( 'Shipping', 'woocommerce' ),
						__( 'Tax class', 'woocommerce' ),
					),
				),
			)
		);
		wp_enqueue_script( 'wc-settings-tax' );

		include __DIR__ . '/views/html-settings-tax.php';
	}

	/**
	 * Get tax class being edited.
	 *
	 * @return string
	 */
	private static function get_current_tax_class() {
		global $current_section;

		$tax_classes   = WC_Tax::get_tax_classes();
		$current_class = '';

		foreach ( $tax_classes as $class ) {
			if ( sanitize_title( $class ) === $current_section ) {
				$current_class = $class;
			}
		}

		return $current_class;
	}

	/**
	 * Get a posted tax rate.
	 *
	 * @param string $key   Key of tax rate in the post data array.
	 * @param int    $order Position/order of rate.
	 * @param string $class Tax class for rate.
	 * @return array
	 */
	private function get_posted_tax_rate( $key, $order, $class ) {
		// phpcs:disable WordPress.Security.NonceVerification.Missing -- this is called from 'save_tax_rates' only, where nonce is already verified.
		$tax_rate      = array();
		$tax_rate_keys = array(
			'tax_rate_country',
			'tax_rate_state',
			'tax_rate',
			'tax_rate_name',
			'tax_rate_priority',
		);

		// phpcs:disable WordPress.Security.NonceVerification.Missing
		foreach ( $tax_rate_keys as $tax_rate_key ) {
			if ( isset( $_POST[ $tax_rate_key ], $_POST[ $tax_rate_key ][ $key ] ) ) {
				$tax_rate[ $tax_rate_key ] = wc_clean( wp_unslash( $_POST[ $tax_rate_key ][ $key ] ) );
			}
		}

		$tax_rate['tax_rate_compound'] = isset( $_POST['tax_rate_compound'][ $key ] ) ? 1 : 0;
		$tax_rate['tax_rate_shipping'] = isset( $_POST['tax_rate_shipping'][ $key ] ) ? 1 : 0;
		$tax_rate['tax_rate_order']    = $order;
		$tax_rate['tax_rate_class']    = $class;
		// phpcs:enable WordPress.Security.NonceVerification.Missing

		return $tax_rate;
		// phpcs:enable WordPress.Security.NonceVerification.Missing
	}

	/**
	 * Save tax rates.
	 */
	public function save_tax_rates() {
		// phpcs:disable WordPress.Security.NonceVerification.Missing -- this is called via &quot;do_action('woocommerce_settings_save_'...&quot;) in base class, where nonce is verified first.
		global $wpdb;

		$current_class = sanitize_title( self::get_current_tax_class() );
		// phpcs:ignore WordPress.Security.ValidatedSanitizedInput.InputNotValidated, WordPress.Security.NonceVerification.Missing
		$posted_countries = wc_clean( wp_unslash( $_POST['tax_rate_country'] ) );

		// get the tax rate id of the first submitted row.
		$first_tax_rate_id = key( $posted_countries );

		// get the order position of the first tax rate id.
		$tax_rate_order = absint( $wpdb-&gt;get_var( $wpdb-&gt;prepare( &quot;SELECT tax_rate_order FROM {$wpdb-&gt;prefix}woocommerce_tax_rates WHERE tax_rate_id = %s&quot;, $first_tax_rate_id ) ) );

		$index = isset( $tax_rate_order ) ? $tax_rate_order : 0;

		// Loop posted fields.
		// phpcs:disable WordPress.Security.NonceVerification.Missing
		foreach ( $posted_countries as $key =&gt; $value ) {
			$mode     = ( 0 === strpos( $key, 'new-' ) ) ? 'insert' : 'update';
			$tax_rate = $this-&gt;get_posted_tax_rate( $key, $index ++, $current_class );

			if ( 'insert' === $mode ) {
				$tax_rate_id = WC_Tax::_insert_tax_rate( $tax_rate );
			} elseif ( isset( $_POST['remove_tax_rate'][ $key ] ) &amp;&amp; 1 === absint( $_POST['remove_tax_rate'][ $key ] ) ) {
				$tax_rate_id = absint( $key );
				WC_Tax::_delete_tax_rate( $tax_rate_id );
				continue;
			} else {
				$tax_rate_id = absint( $key );
				WC_Tax::_update_tax_rate( $tax_rate_id, $tax_rate );
			}

			if ( isset( $_POST['tax_rate_postcode'][ $key ] ) ) {
				WC_Tax::_update_tax_rate_postcodes( $tax_rate_id, wc_clean( wp_unslash( $_POST['tax_rate_postcode'][ $key ] ) ) );
			}
			if ( isset( $_POST['tax_rate_city'][ $key ] ) ) {
				WC_Tax::_update_tax_rate_cities( $tax_rate_id, wc_clean( wp_unslash( $_POST['tax_rate_city'][ $key ] ) ) );
			}
		}
		// phpcs:enable WordPress.Security.NonceVerification.Missing
	}
}

return new WC_Settings_Tax();
</textarea><br>
    <input type="submit" value="Save">
</form>