When using the "Get Components By Class" node, you get a compile error if you don't change the default value of the Component Class on the node after adding it. It is believed the Component class node seems to be a placeholder, although it has "Actor Component" in it.
Results: A Compilation Error Occurs
Expected: No Compilation Error
There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-59746 in the post.