A set of objects which can be instantiated Inline in the Editor that contain an array of References to their children that have nested Blueprint objects inheriting from a Native Base Class can cause references to an object using a cast to its owner to be lost after the editor is restarted.
Result: The reference has been set back to "None"
Expected: The element would still be set to "Node_Implemented" 
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-59135 in the post.
| 1 | 
| Component | UE - Gameplay - Blueprint | 
|---|---|
| Affects Versions | 4.19.2 | 
| Target Fix | 4.21 | 
| Created | May 15, 2018 | 
|---|---|
| Resolved | Sep 12, 2018 | 
| Updated | Jan 16, 2019 |