public FormState::disableCache() Prevents

public FormState::disableRedirect($no_redirect = TRUE)

public FormState::setButtons(array $buttons) Stores

This is not a special key, and no specific support is provided for it in the Form API. By tradition it was the location where application-specific data was stored for communication

public FormCache::getCache($form_build_id, FormStateInterface $form_state)

Contains references to details elements to render them within vertical tabs. This property is uncacheable.

public FormStateDecoratorBase::setLimitValidationErro

public FormBuilder::doBuildForm($form_id, &$element, FormStateInterface

public FormStateDecoratorBase::isBypassingProgrammedA

Defines an exception used, when the POST HTTP body is broken. Hierarchy class \Sy