Can I group received emails in Sierra? In Apple Mail v.10.3 (3273), is there a way to see received emails grouped together by sender name and subject as in Mail v.7 (running under Mavericks v.10.9.5) where I was able to click on the "#>>" (the number of emails in the group and 2 right-facing arrows) to expand or collapse the list? Thank you.

MacBook Pro (Retina, 15-inch, Late 2013), macOS Sierra (10.12.4), Time Capsule; AGT784WNV DSL Gateway
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