Apparently GitHub is working on a "new experience" for the pull request review view.

Unfortunately in its current state it hides individual commits even further.

(if you then select a single commit you're back to the "old experience" for now)

A dropdown in GitHub's UI labeled "All changes".
The dropdown then shows "All changes" (selected) and "Specific commit..."A overlay selector in GitHub's UI.
Titled "Pick one or more commits" with a list below listing the commits with their message, commit id, author and relative timestamp ("yesterday"). Every commit has an (unmarked) checkbox.
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