Allow existing customers with license key - Safari WebExtension

Hello,

I have a browser extension that is already released for other browsers, and I want to start releasing for Safari as well, and I have a few questions about the payments system.

My extension allows users to unlock features by making a payment through Stripe or PayPal and receiving a license key.

For Safari I want to use Apple’s IAP system as I already know that this is a requirement but I also want to allow people that already purchased the license through other browsers to use it with Safari.

So my question, Am I allowed to allow people bring their license keys purchased from other browsers?

Throughout the Safari extension I will only use Apple’s IAP system and offer the same price as on other browsers. So I will not ”reward” people with discounts if they use other payment processors outside of Safari.

Thank you!