Variable Product types not showing as selectable variants on Facebook

[johndcoy]

🔎 Isolate the bug

• [x] I have confirmed this occurs in the most recent version of WordPress, WooCommerce, and Facebook for WooCommerce.
• [x] I have confirmed this occurs when only WooCommerce and Facebook for WooCommerce are active and when using a default WordPress or WooCommerce theme.

✍️ Describe the bug

Variable products assigned to the same item_group_id do not show as variants on Facebook. Variable products are shown similarly to simple products with a link to the product page without the option to link to a specific variation.

Items are grouped properly within the catalog manager:

However, the product page on the show only links to the parent product:

I believe the issue is specific to the product not being sent to Facebook with the attribute assigned. Per Facebook's documentation ( see section "How to add variants using a data feed" ) you'll see an example with tables for how not to send data:

Screenshot link: https://d.pr/i/ahfj43

When viewing the CSV from feedURL: object the products are not assigned to attributes:

Screenshot link: https://d.pr/i/aUtFZr

See this issue for obtaining feedURL: https://github.com/woocommerce/facebook-for-woocommerce/issues/2392

🚶‍♀️ Steps to reproduce

1. Create a variable product.
2. Assign that product global and/or product attributes.
3. Create variations from that attribute and confirm each variation has attributes assigned. Do not use the "Any..." attribute.
4. Publish the product and view it on Facebook
5. See the issue that none of the attributes show.

✔️ Expected behavior

The expected behavior is for the item to show selectable variations that "View on Website" would link directly to:

Screenshot link: https://d.pr/i/3hGEWO