Automatic tax calculation critical bug when using PayPal

When checking out with the PayPal Gateway Plugin and with only virtual products in the cart, the billing address fields Country and Post Code become optional instead of the default mandatory.

This creates a conflict with automatic tax calculations as these fields are required for that calculation.

Currently customers can checkout without paying tax when it should be applicable, so this is a critical bug for many stores.

I have verified the PayPal Gateway plugin as the cause by reverting to Twentynineteen theme, deactivating all plugins and reactivating one by one while refreshing the checkout page. Only when the WooCommerce PayPal Gateway plug-in is activated does this bug occur, and only when no physical products are in the cart.

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