https://api.drupal.org/api/drupal/core%21modules%21image%21src%21Form%21ImageStyleFlushForm.php/9
ImageStyleFlushForm.php | Drupal API
phpdrupalapi
https://api.drupal.org/api/drupal/core%21modules%21image%21src%21Form%21ImageStyleFlushForm.php/function/ImageStyleFlushForm%3A%3AsubmitForm/11.x
function ImageStyleFlushForm::submitForm | Drupal API
functiondrupalapi