> OK, I think I understand the problem: you don't have the Noto Color
> Emoji font installed.  Install it, and the display will be according
> to expectations.

I followed:

https://jenciso.github.io/blog/how-setup-your-noto-color-emoji-fonts/

But this font is not used by Emacs for unknown reasons, strange.

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Warning: Content may be disturbing to some audiences
I strongly condemn Putin's war of aggression against the Ukraine.
I support to deliver weapons to Ukraine's military. 
I support the ban of Russia from SWIFT.
I support the EU membership of the Ukraine. 
https://addons.thunderbird.net/en-US/thunderbird/addon/gmail-conversation-view/