tabs

my_custom.links.task.yml:

/**
* Implements hook_menu_local_tasks_alter().
*/
function MYMODULE_menu_local_tasks_alter(&$data, $route_name, RefinableCacheableDependencyInterface $cacheability) {
 $current_user = \Drupal::currentUser();
 if ($current_user->hasRole('administrator')
   || $current_user->hasRole(

Needs minimum 2 subtabs! 

custom.links.task.yml:

Create mymodule.links.task.yml and add some lines

/**
* Implements hook_local_tasks_alter().
*/
function EXAMPLE_local_tasks_alter(&$local_tasks) {
  $local_tasks['entity.user.edit_form']['title'] = new TranslatableMarkup('Personal data');
}

/**
* Implements hook_local_tasks_alter().
*/
function EXAMPLE_local_tasks_alter(&$local_tasks) {
 unset($local_tasks['user.register']);
}