Ticket #31771: 31771.diff

src/wp-includes/wp-db.php

@@ -2219 +2219 @@
                 foreach ( $columns as $column ) {
                         if ( ! empty( $column->Collation ) ) {
                                 list( $charset ) = explode( '_', $column->Collation );
+
+                                // If the current connection can't support utf8mb4 characters, let's only send 3-byte utf8 characters.
+                                if ( 'utf8mb4' === $charset && ! $this->has_cap( 'utf8mb4' ) ) {
+                                        $charset = 'utf8';
+                                }
+
                                 $charsets[ strtolower( $charset ) ] = true;
                         }