Understanding "CreateTag"

Dear Helpers,

I’m completely new to Select2. I understand that the createTag-Callback is triggered each time when I press a key in the search-field. Even if I type a word which is already in the list.
The “select2:select”-Event is triggered each time an option is selected
Is there an event, which is triggered, when a new Tag is added to the list?

What do I try to achieve:

  1. User can choose from list or create a new option/tag
  2. The new Tag should be send via ajax to server (php) and stored in database
  3. Options of all select2 elements with a certain class should be updated with new options

Thank you very much!

All the best, Phantom