Paystack blocks iframes, so checkout uses a popup beside the sheet/modal chrome. Opening about:blank on the user tap keeps that window from being blocked after the async initiate response.
Paystack checkout.paystack.com returns X-Frame-Options: SAMEORIGIN, so the shared sheet opened empty. Keep mobile sheet/desktop modal chrome, launch checkout in a named window with a Continue CTA fallback, and escape payment-return via window.opener or top.
isaacclad