Question Mark Instead Of Emoji In macOS Messages

Had this problem. When I send a message with emoji -- or receive a message -- in the right-hand pane, in the current conversation, a question mark in a box is displayed instead of emoji. But the left-hand column of list of conversations displays the normal Emoji.

Tried these three solutions, with no resolution of the problem:

-- .sudo atsutil databases -remove

-- .FontBook > File > Restore Standard Fonts

-- .Restart Mac in safe mode.

Then I looked again to see what is in

-- .Messages > Menu > Preferences > General

Found that the option titled 'Text Size' now has a dropdown to select a font face & size, instead of just a slider for size as it once had.

When I.opened 'Text Size', it was set to "System Font 15" -- and, that entry was grayed out ... as if it was not a valid choice. So, I picked my favorite font & size, and presto! -- emojis all display fine.

This solved the problem. .

-- .Messages > Menu > Preferences > General > Text Size -- pick a valid font

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iMac (2017)

macOS High Sierra 10.13.6 (17G3025)

Messages Version 11.0 (5500)

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