sslFailClosedSupported

SslFailClosedWebViewClient really is installed on the WebView, and really does cancel the load.

False. Nothing in this module installs or verifies TLS handling on the iOS WebView, so there is no guarantee here to report as kept — only an expectation of WKWebView's defaults.

Whether this platform's sslFailClosedWebViewParams actually enforces fail-closed TLS handling on the checkout WebView. True on Android, false on iOS.

Public API rather than a comment on purpose. The iOS actual of sslFailClosedWebViewParams returns null and argues in its KDoc that WKWebView fails closed by default — which may well be true, but it is an assumption about a third party's behaviour, not something this module checks, enforces or can promise. A caller with a payment session to protect needs to be able to read that difference at runtime and decide, exactly the way canShareImage() in :feedback lets a caller decide rather than hope.

What a caller does with a false is its policy, not this module's: refuse to open the webview, fall back to a native SDK, or accept the risk and log it. What it must not have to do is read source to discover the guarantee is not there.

if (!sslFailClosedSupported()) return PaymentResult.Unavailable("tls_unenforced")
HostedCheckoutScreen(checkoutUrl, matchReturn, onResult)