WooCommerce custom product tab with admin field

<?php
/**
 * Custom "Care guide" product tab.
 *
 * @package Acme_Core
 */

defined( 'ABSPATH' ) || exit;

// 1. Admin: a textarea in the General tab of the product data box.
add_action( 'woocommerce_product_options_general_product_data', static function (): void {
	woocommerce_wp_textarea_input( array(
		'id'          => '_acme_care_guide',
		'label'       => __( 'Care guide', 'acme-core' ),
		'description' => __( 'Shown in its own tab on the product page.', 'acme-core' ),
		'desc_tip'    => true,
	) );
} );

// 2. Save it. WooCommerce already verified the nonce and capability for this hook.
add_action( 'woocommerce_admin_process_product_object', static function ( WC_Product $product ): void {
	$value = isset( $_POST['_acme_care_guide'] ) // phpcs:ignore WordPress.Security.NonceVerification.Missing
		? wp_kses_post( wp_unslash( $_POST['_acme_care_guide'] ) ) // phpcs:ignore WordPress.Security.NonceVerification.Missing
		: '';
	$product->update_meta_data( '_acme_care_guide', $value );
} );

// 3. Front end: add the tab only when the product has content.
add_filter( 'woocommerce_product_tabs', static function ( array $tabs ): array {
	global $product;

	if ( $product instanceof WC_Product && '' !== trim( (string) $product->get_meta( '_acme_care_guide' ) ) ) {
		$tabs['acme_care'] = array(
			'title'    => __( 'Care guide', 'acme-core' ),
			'priority' => 25,
			'callback' => 'acme_care_tab_content',
		);
	}
	return $tabs;
} );

function acme_care_tab_content(): void {
	global $product;
	echo '<h2>' . esc_html__( 'Care guide', 'acme-core' ) . '</h2>';
	echo wp_kses_post( wpautop( (string) $product->get_meta( '_acme_care_guide' ) ) );
}