• API: Form API in Drupal 8 Form and render elements
    • Render: Render API overview Render API
    • Cache: ..cacheability vary-user-agent
    • Element: namespace Drupal\Core\Render\Element
  • Multi Step Form: search in core for MultiStepForm
    • Building a Multi-Page Wizard-like Form
    • How to Build Multi-step Forms
    • ..with backwards button Drupal 7 multistep node forms are easy
  • tabledrag: Referenz
    • Draggable tables do not work on touch screen devices