It’s now possible to bulk select authors to an author list 
Rather than adding each author one by one, you can now add up to 5,000 authors to a list at once - this is particularly useful if you create author lists from Explore searches that yield many results.
Note: This feature allows you to select up to 5,000 authors at a time. If more than 5,000 authors are selected, the app will notify you and give you the option to cancel (to refine the search) or add the first 5,000 authors to your list.
