Pro Sites: Paypal IPN URL need to be entered where?

Hi WPMUDEV

In pro sites it is written the following:

To use PayPal Express Checkout or Pro you must manually turn on IPN notifications and enter your IPN url (https://my.domain/wp-admin/admin-ajax.php?action=psts_pypl_ipn) in your PayPal profile (you must also do this in your sandbox account when testing).

Where does this URL need to be entered exactly?

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At PM-Memebership Pro Plugin it is written just the opposite:

This URL is passed to PayPal for all new charges and subscriptions. You SHOULD NOT set this in your PayPal account settings.
https://my.domain/wp-admin/admin-ajax.php?action=ipnhandler

So if you are using in your multisite both plugins they would conflict with each other. Right?

Kind regards

Andi