Hi Genova,
Thanks for report! I was able to reproduce this in 4.9.0. It looks like we have a new Note system, but I don’t see any reason for this particular instance. I’ve created a bug report for issue (UE-20613), and I’ll let you know when I see an update on it.
In meantime, Note shouldn’t interfere with functionality of an array input. Please let us know if you see any additional problems with this. Thanks again!