feat(android): expose allowedBrowserPackages option for web authentication

[mrbrentkelly]

Changes

Adds an allowedBrowserPackages option to NativeAuthorizeOptions that restricts which browsers can handle the web authentication flow on Android.

This exposes the browser filtering capability already present in the underlying Auth0.Android SDK via BrowserPicker and CustomTabsOptions through the React Native bridge.

Motivation

Firefox on Android does not correctly handle App Link redirects, causing the Auth0 login flow to fail silently — the browser renders the callback URL as a page rather than handing off to the app. This is a known Firefox bug.

The same issue was reported and resolved for the Flutter SDK in auth0/auth0-flutter#392 by exposing an allowedBrowsers option. This PR brings the same capability to React Native.

Behaviour

When allowedBrowserPackages is set on Android:

• The user's default browser is in the list → it is used
• The user's default browser is not in the list, but another allowed browser is installed → that browser is used instead
• No allowed browser is installed → a0.browser_not_available error is returned

On iOS the option is ignored.

Usage

await auth0.webAuth.authorize(parameters, {
  allowedBrowserPackages: [
    'com.android.chrome',
    'com.chrome.beta',
    'com.microsoft.emmx', // Edge
    'com.brave.browser',
    'com.sec.android.app.sbrowser', // Samsung Internet
  ]
});

Files changed

• src/types/platform-specific.ts — adds allowedBrowserPackages?: string[] to NativeAuthorizeOptions with JSDoc indicating Android-only
• src/specs/NativeA0Auth0.ts — adds parameter to TurboModule spec
• src/platforms/native/bridge/NativeBridgeManager.ts — passes option through to native layer
• android/src/main/java/com/auth0/react/A0Auth0Module.kt — implements BrowserPicker via CustomTabsOptions
• android/src/main/oldarch/com/auth0/react/A0Auth0Spec.kt — updates old arch abstract method signature

References

• Firefox bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1976809
• Equivalent Flutter fix: Firefox users seeing "not found" on Android, both login and logout auth0-flutter#392
• Auth0.Android BrowserPicker: Feat: Filter allowed CustomTabs browsers Auth0.Android#353

[subhankarmaiti]

Hey @mrbrentkelly, thanks for this PR! I've reviewed it against the underlying Auth0.Android SDK and have a few things that need to be addressed before we can merge.

1. The changes should also needs to be added in logout flow otherwise the logout will still be used in users default browser
2. Please change the name to allowedBrowserPackages to keep it same as all the layers.
3. Please add supported test cases
4. Looks like iOS bridge might going to crash at runtime as the changes added a new parameter in the iOS webauth call

[mrbrentkelly]

Hey @subhankarmaiti, I think I've addressed all your comments if you want to take a second pass.

Thanks for calling out the iOS side, I had noticed as well it was crashing so I've updated the appropriate method signatures in A0Auth0.mm 👍