😛wpadminbar on/of (ok)

C:\xampp74\htdocs\wpclidemo\wp-content\themes\namkhoa\functions.php

add_filter('show_admin_bar', 'remove_admin_bar'); // Remove Admin bar

C:\xampp74\htdocs\wpclidemo\wp-content\themes\namkhoa\header.php

<?php wp_body_open();?>

<?php
//wp_body_open hook from WordPress 5.2
if (function_exists('wp_body_open')) {
    wp_body_open();
} else {
    do_action('wp_body_open');
}
?>