Allow editors to edit the content of the privacy policy page

allow-privacy-page-edits.php

<?php
/**
 * Allow Privacy Policy Page Edits
 *
 * @package           AllowPrivacyPolicyPageEdits
 * @author            Bernhard Kau
 * @license           GPL-2.0-or-later
 *
 * @wordpress-plugin
 * Plugin Name:       Allow Privacy Policy Page Edits
 * Plugin URI:        https://gist.github.com/2ndkauboy/741683cf08072b9b37a395a078862e49
 * Description:       Allow editors to edit the content of the privacy policy page.
 * Version:           1.0.0
 * Requires at least: 4.9
 * Author:            Bernhard Kau
 * Author URI:        https://kau-boys.de
 * License:           GPL v2 or later
 * License URI:       https://www.gnu.org/licenses/gpl-2.0.html
 */

/**
 * Adjusts the capabilities required to edit the privacy policy page.
 *
 * @param string[] $caps Primitive capabilities required of the user.
 * @param string $cap Capability being checked.
 *
 * @return string[] Primitive capabilities required of the user.
 */
function allow_privacy_policy_page_edits( $caps, $cap ) {
	if ( $cap !== 'manage_privacy_options' ) {
		return $caps;
	}

	return array_diff( $caps, [ 'manage_options' ] );
}
add_filter( 'map_meta_cap', 'allow_privacy_policy_page_edits', 10, 2 );

For multisite its manage_network not manage_options.

I needed to do this for shop managers so I also wanted to add the cap to them and settled on this:

add_action( 'admin_init', function () {
    foreach ( [ 'editor', 'shop_manager' ] as $role_name ) {
        $role = get_role( $role_name );
        if ( $role ) {
            $role->add_cap( 'manage_privacy_options' );
        }
    }
} );

add_filter( 'map_meta_cap', function ( array $caps, string $cap ) : array {
    if ( 'manage_privacy_options' !== $cap ) {
        return $caps;
    }

    $admin_cap = is_multisite() ? 'manage_network' : 'manage_options';

    return array_values( array_diff( $caps, [ $admin_cap ] ) );
}, 10, 2 );

If you use this on your site you can remove the add_action after you have added it, then visited the admin panel once. You need to keep the map_meta_cap for every request though.