title: jQuery Migration. No equivalent to "then"
body: <p>Hi I have been working on updating jQuery from 1.11 to 3.3.
  I installed jQuery migration script which pointed out many of the differences that needed to be made. However, I have found no alternatives to this issue.</p>
  
  <p>I have a callback in the "then" function that is not run immediately (synchronous), so I searched in the <a href="https://jquery.com/upgrade-guide/3.0/#callback-invocation" rel="nofollow noreferrer">guide</a>! it recommends you to convert it to a callback to "done". However, the intention is different, I want to concatenate the promises not use the original promise.
  I would use "pipe" but it has been <a href="https://api.jquery.com/deferred.pipe/" rel="nofollow noreferrer">deprecated</a>! in favor of "then" so what do I use to keep the sync and at the same time be able to concatenate promises?</p>
  
  <p>Thanks</p>