Yaml: Last list entry used instead of showing top level yaml items

Question

Both of the following (A) and (B) are correct yaml and should render the same as follows:

A)

@startyaml
compute:
  - name: worker
    replicas: 2
@endyaml

B)

@startyaml
compute:
- name: worker
  replicas: 2
@endyaml

Unexpectedly, case B ignores the holding compute: entry, showing only the list entry as follows:

Edits: Fix formatting