As you may already know, the traditional method of implementing drag & drop is broken in 4.17.1. (Unreal Engine Issues and Bug Tracker (UE-49100)) and has a target fix of 4.18.
I don’t think the importance of the issue has been noticed by the team. This issue will be affecting most projects which contain some sort of Drag & Drop, and should be fixed in 4.17.2.
I have spoken with various members of the community and they also believe that this isn’t the kind bug to be left to the next major version. For a lot of us, we cannot wait a few months for 4.18 - we need this hotfixed.