Cannot Clear List with GraphQL - Dgraph execution failed because Got unsupported type for list

Is this bug being tracked?
I’m trying to update the a list as you suggested here, but I got this error

In my case, Foo.items is a list of another type, something like this:

type Foo {
  items: [FooItem!]
}

type FooItem {
  bar: String
  baz: String!
}