Emoji replaced with ???? although DB table charset is utf8mb4

Hi,

my WP installation insists on replacing emoji with question marks.
More specifically, modern emoji get replaced with 4 question marks “????” while some (older?) emoji display just fine. I suspect that 3-byte emoji are fine, and 4-bytes emoji are destroyed.

The thing is, my DB charset is utf8mb4 , the wp_posts table columns are all utf8mb4 , DB_CHARSET is utf8mb4 in wp-config.php.
(See https://imgur.com/a/29a7pkT)

Funny enough, if I insert emoji in the post_content column for a given post from phpMyAdmin, they remain as emoji, visible as such in phpMyAdmin.
However, if I reload the page in the WP page editor, they get replaced with the dreaded “????” and the next save replaces them in the DB.
If I simply load the page in the frontend, I get the “????” , however the proper emoji remain in the DB, as shown by phpMyAdmin.

So, it looks like WP is somehow “translating” the emoji to/from the DB and fails to do so ?

Any help to display my emoji will be greatly appreciated !
Thanks !

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