Flutter Android: android:usesCleartextTraffic="false"+ Network Security Config not blocking HTTP requests

I want my Flutter Android app to reject all clear‑text HTTP traffic (i.e. only allow HTTPS).

AndroidManifest.xml

xml

<application…  android:usesCleartextTraffic="false"  android:networkSecurityConfig="@xml/network_security_config">…</application>

Network Security Config (android/app/src/main/res/xml/network_security_config.xml)

xml

<?xml version="1.0" encoding="utf-8"?><network-security-config><!-- Disallow all cleartext --><base-config cleartextTrafficPermitted="false"/></network-security-config>

What happens instead:Despite those settings, I am still able to fetch an HTTP URL in Dart/Dio, for example:

dart

final response = await Dio().get('http://httpstat.us/200');print(response.statusCode); // prints 200