When exactly does jquery.ajax trigger an error callback?

Question

I can not find this in the documentation. I also skipped the jquery source and can no longer find the information.

Using jquery.ajax, when can I expect the failure callback to be triggered?

In addition to the following:

• connection problem (for example, a lost connection with a mobile device)

• server is down and not responding

  // EDIT: added after comments, thank you very much @charlietfl:

• http error code equal to or more than 400

• missing CORS headers

What are the other cases where jquery will trigger a fail callback?

Answer 1

, 4xx 5xx, . .