Facebook for WooCommerce

CAPI purchase events are not tracked on iOS when external payment provider is used. FBfWC relies on WC session, but user loses session.

User flow:
1) User clicks FB ad in Facebook or Instagram app and woocommerce store opens within FB / Insta.
2) User purchases product in Woocommerce store
3) User is sent to external payment provider (different app, like paypal)
4) User completes payment and is sent back to Native iOS Safari, not to browser window within FB or Insta app
5) User does not have a WC->session, because of new browser, so inject_purchase_event() does not fire

Expected behaviour: Please don’t rely on a session when working with payment providers. Save the _fbc in the order meta table and trigger the CAPI purchase event on the woocommerce_checkout_order_processed hook.
Also, don’t rely on the user opening the thank you page, the user could close the browser after completing payment, never seeing the thank you page.

Please see this thread for more debugging and evidence:
https://wordpress.org/support/topic/capi-issues/

Please fix this, it is impossible to track purchase conversions with FB ads and Woocommerce, which is sort of the whole purpose of this plugin.

Another note: It seems somebody “fixed” this not too long ago:
= 2.6.24 – 2022-09-27 =
* Fix – Track purchase event flag in session variable instead post meta table.