I have hosted my AASA file in https://powerbrowser.app/.well-known/apple-app-site-association in signed format as per documentation.
I still can not see open in app button when open a link by long press.
By the way i have activated 'Associated Domains' and put proper entitlements as per documantation.
Have you read through TN3155 Debugging universal links? It has a bunch of hints and tips on debug to… well… debug universal links (-:
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Quinn “The Eskimo!” @ Developer Technical Support @ Apple
let myEmail = "eskimo" + "1" + "@" + "apple.com"