PayPal Drop-in shows blank page in TikTok / social media in-app browsers (iOS & Android)

[dePablobernat]

Describe the bug

When a user opens a merchant page via a TikTok, Instagram, or Facebook link (inside the app's built-in browser) and attempts to pay with PayPal via the Adyen Drop-in, the PayPal authentication overlay opens but displays a permanently blank white page. The payment flow never completes.

This affects a large and growing segment of users since social media in-app browsers are the primary traffic source for many merchants.

Steps to reproduce

1. Open TikTok on iOS or Android
2. Tap a link to a merchant page with Adyen Drop-in + PayPal enabled
3. Proceed to checkout and select PayPal
4. Click the PayPal button
5. A browser overlay opens → blank white page, PayPal never loads

Expected behavior

PayPal authentication loads and the user can complete payment.

Actual behavior

PayPal overlay opens with a permanently blank white page. No error is shown to the user. Payment is impossible.

Root cause (investigated)

PayPal's JS SDK renders its button inside a cross-origin iframe. When clicked, it executes:

const windowRef = window.open('about:blank', ...)
windowRef.location.replace('https://www.paypal.com/...')

In TikTok's WebView (WKWebView on iOS), window.open succeeds but the subsequent location.replace from about:blank → paypal.com is silently blocked — resulting in a blank overlay.

This was confirmed by a PayPal engineer in mozilla-mobile/firefox-ios#30098 as a cross-origin iframe → popup restriction.

PayPal's own SDK (@krakenjs/belter) detects TikTok as supportsPopups=false, but FUNDING.PAYPAL does not have requires.popup set — so the button remains eligible and visible, leading users into a broken flow with no feedback.

We also confirmed there is no PayPalConfiguration option in the current Drop-in API to switch to a redirect-based flow.

This is a widespread, actively reported issue

• mozilla-mobile/firefox-ios#30098 (Oct 2025, last activity Mar 2026) — PayPal blank page in Firefox iOS confirmed by a PayPal engineer as a cross-origin iframe window.open restriction. Same root cause.
• paypal/paypal-js#534 (active through Nov 2025) — PayPal button opens overlay but popup is empty/blank. Multiple reporters across different browser environments.
• DEV Community — PayPal Smart Buttons in 2025: about:blank flash + never-closing popup (Nov 2025) — documents the about:blank flash and blank popup as still active problems in 2025.
• flutter/flutter#93425 (still receiving comments Jul 2025) — PayPal button in WebView opens blank page on iOS. No resolution.

PayPal/Braintree themselves acknowledge this is systemic — they maintain dedicated libraries (popup-bridge-ios, popup-bridge-android) specifically for WebView popup failures. These are not accessible to merchants using the Adyen Drop-in.

Proposed solution

Could Adyen expose a redirect mode for the PayPal component that bypasses the JS SDK popup flow? For example:

paymentMethodsConfiguration: {
  paypal: {
    showPayButton: true,
    redirectMode: true, // full-page redirect instead of popup
  }
}

When active, the flow would be:

1. Create PayPal order server-side
2. Return the PayPal approve URL
3. Full-page redirect to https://www.paypal.com/checkoutnow?token=...
4. Return via the existing returnUrl redirect handler (already supported in Drop-in)

Alternatively, exposing a way to pass data-popups-disabled="true" to the PayPal SDK script tag (which already exists in paypal-sdk-constants as SDK_DATA_ATTRIBUTES.POPUPS_DISABLED) would allow merchants to opt into PayPal's own in-page flow for popup-restricted environments.

Environment

• @adyen/adyen-web: 6.22.0
• Affected: TikTok in-app browser (iOS + Android), Instagram in-app browser, Facebook in-app browser
• Not affected: Safari, Chrome, Firefox (standard browsers)

[sponglord]

@dePablobernat - we are asking our PayPal team about whether there is a way to force a redirect flow