Code shared by CodePotent; goes in your theme functions file.
function codepotent_debug_notifier_register_admin_bar() {
if (!current_user_can('manage_options')) {
return;
}
global $wp_admin_bar;
$label = esc_html__(' Debugging DISABLED ', 'codepotent-debug-notifier');
if (defined('WP_DEBUG')) {
if (WP_DEBUG == true) { // Loose comparison is intentional here.
$label = '<div style="color: #f00;">'.esc_html__(' Debugging ENABLED ', 'codepotent-debug-notifier').'</div>';
}
}
$wp_admin_bar->add_menu([
'parent' => false,
'id' => 'codepotent-debug-notifier',
'title' => $label
]);
}
add_action('wp_before_admin_bar_render', 'codepotent_debug_notifier_register_admin_bar');