WooCommerce Mix and Match Products - "PHP Notice: Undefined property" fatal error

Overview of the issue

With the latest versions of WCML and WooCommerce Mix and Match Products enabled, the following fatal error occurs:

PHP Notice: Undefined property: WCML_Mix_and_Match_Products::$woocommerce_wpml in /var/www/somedomain.com/html/wp-content/plugins/woocommerce-multilingual/compatibility/class-wcml-mix-and-match-products.php on line 29

Workaround

This issue will be resolved in the next release of WooCommerce Multilingual.

Affected users can resolve the issue until then by correcting the following line:
wp-content/plugins/woocommerce-multilingual/compatibility/class-wcml-mix-and-match-products.php:29

From:

$original_product_id = $this->woocommerce_wpml->products->get_original_product_id( $post_id );

To:

$original_product_id = $woocommerce_wpml->products->get_original_product_id( $post_id );

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