Token Portability on Apple devices

I have a use case where I want to retrieve a third-party access token and pass it between servers to allow different services to make API calls. But when looking through the third-party docs, I found this note:

"One important aspect to understand about access tokens is that most tokens are portable. However, Apple does not allow moving tokens to servers."

It's found here: https://developers.facebook.com/docs/facebook-login/guides/access-tokens#portabletokens

Does anyone have more information on what this means? Has anyone had issues with passing tokens between clients/servers or servers/servers on Apple devices?

Thanks!

Token Portability on Apple devices
 
 
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