The folks at RankRanger spotted and posted on Twitter Google testing a new form of query expansion for related queries under the featured snippets. We saw this before about a year ago but it hasn’t come up much since.
In short, Google is listing other queries, that help the searcher expand and refine their search to give you a more precise and detailed featured snippet answer.
Here is a screen shot which you can click on to enlarge:

No surprise here of course…
Forum discussion at Twitter.

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