Update index.mdx

Author: krystofwoldrich

docs/platforms/react-native/session-replay/privacy/index.mdx

@@ -25,6 +25,12 @@ Sentry.mobileReplayIntegration({
 
 _Make sure your Sentry React Native SDK version is 5.36.0, 6.3.0 and up_
 
+<Alert level="warning">
+
+If you are manually initializing native SDKs before JS, the React Native text and images won't be automatically masked. For the current state of this issue and example workaround, please see [GH-4853](https://github.com/getsentry/sentry-react-native/issues/4853).
+
+</Alert>
+
 ## Mask and Unmask Components
 
 You can choose which views you want to mask or unmask by using the `Mask` or `Unmask` components.