anchor.diff:  
   ==============================
   
  +
  +===== Wait for completion
  +
   The task API can also be used to wait for completion of a particular task. The
   following call will block for 10 seconds or until the task with id
   `oTUltX4IQMOUUVeiohTt8A:12345` is completed.
  
positive.code: --------------------------------------------------
  // CONSOLE
  
  [float]
  [[task-cancellation]]
  ==== Task Cancellation
  
  If a long-running task supports cancellation, it can be cancelled with the cancel 
  tasks API. The following example cancels task `oTUltX4IQMOUUVeiohTt8A:12345`:
  
negative.code: --------------------------------------------------
  // CONSOLE
  
  
  ===== Identifying running tasks
  
  The `X-Opaque-Id` header, when provided on the HTTP request header, is going to 
  be returned as a header in the response as well as in the `headers` field for in 
  the task information. This allows to track certain calls, or associate certain 
  tasks with a the client that started them:
  
  [source,sh]
  --------------------------------------------------
  