Email translation lost when being redirected to the thank you page

[TommyKolkman]

At first let me say I know that you guys are not officially supporting Polylang -- I'm just investigating an issue with it and am a bit lost which plugin is responsible.

Situation:

• woocommerce 8.0.1
• polylang-wc 1.9.2
• polylang-pro 3.5.3
• mollie-payments-for-woocommerce 7.4.0

When a payment is redirected back via the webhookUrl, the order is updated to processing, of course. On that moment, the 'polylang-wc' plugin adds a filter that sets the language:

	/**
	 * Setups actions related to emails sent to a customer.
	 *
	 * @since 1.7
	 *
	 * @return void
	 */
	protected function customer_emails_init() {
		/**
		 * Filters the actions used to send translated customer emails related to an order.
		 * The actions in the list must pass a `WC_Order` or order id as first parameter.
		 *
		 * @since 1.6
		 *
		 * @param string[] $email_actions Array of actions used to send order emails.
		 */
		$actions = apply_filters(
			'pllwc_order_email_actions',
			array(
				// Completed order.
				'woocommerce_order_status_completed_notification',
				// Customer note.
				'woocommerce_new_customer_note_notification',
				// On hold.
				'woocommerce_order_status_failed_to_on-hold_notification',
				'woocommerce_order_status_pending_to_on-hold_notification',
				'woocommerce_order_status_cancelled_to_on-hold_notification',
				// Processing.
				'woocommerce_order_status_cancelled_to_processing_notification',
				'woocommerce_order_status_failed_to_processing_notification',
				'woocommerce_order_status_on-hold_to_processing_notification',
				'woocommerce_order_status_pending_to_processing_notification',
				// Refunded order.
				'woocommerce_order_fully_refunded_notification',
				'woocommerce_order_partially_refunded_notification',
			)
		);

		foreach ( $actions as $action ) {
			add_action( $action, array( $this, 'before_order_email' ), 1 ); // Switch the language for the email.
			add_action( $action, array( $this, 'after_email' ), 999 ); // Switch the language back after the email has been sent.
		}
	}

	/**
	 * Sets the email language depending on the order language.
	 * Hooked to order notifications.
	 *
	 * @since  0.1
	 *
	 * @param int|array|WC_Order $order Order or order ID.
	 * @return void
	 */
	public function before_order_email( $order ) {
		if ( is_numeric( $order ) ) {
			$order_id = $order;
		} elseif ( is_array( $order ) ) {
			$order_id = $order['order_id'];
		} elseif ( is_object( $order ) ) {
			$order_id = $order->get_id();
		}

		if ( ! empty( $order_id ) ) {
			$lang = $this->data_store->get_language( $order_id );
			$language = PLL()->model->get_language( $lang );
			if ( $language ) {
				$this->set_email_language( $language );
			}
		}
	}

	/**
	 * Restores the current language after the email has been sent.
	 * Hooked to order and user notifications.
	 *
	 * @since 0.1
	 *
	 * @return void
	 */
	public function after_email() {
		if ( empty( $this->previous_languages ) ) {
			return;
		}

		$previous = array_pop( $this->previous_languages );

		if ( $previous['switched'] ) {
			restore_previous_locale();
		}

		PLL()->curlang = $previous['language'];
	}

This does work, I can confirm from making a status change on an order in the back-end. With other payment methods it works too.

However, when using Mollie it does not.

So I am investigating:

• Is the Mollie plugin actually firing woocommerce_order_status_pending_to_processing_notification, or does it not use that at all?
• Could the prioritization of the filters be in the wrong order of some sorts?
• Would there be a workaround?

The clients customers are receiving default mails now, while they should get them in the site's language.

Hope you guys can help.

[TommyKolkman]

Bumping this: anyone?