Field state clean up fails for Entity Reference fields

I noticed some strange behavior while creating nodes. Node create forms are not presented empty under certain circumstances. As far as I am concerned it only applies to fields of type entity reference.

Steps to reproduce:

1. install plain drupal 8
2. install latest IEF dev version
3. create 3 content types (A, B and C)
4. make A reference B (cardinality > 1)
5. make B reference C (cardinality does not matter)
6. set form display for both references to "Inline Entity Form - Multiple Values"
7. now go on and start creating a node of type A
8. create a referenced node of type B using IEF widget (also create node of type C in the process). Save B!
9. click on "create new node" (to create another reference of type B)
10. you should be presented a form which has the reference field to C pre filled (although it should be empty)