Network module fails to switch to cellular link after Wi-Fi has been disabled

If an application that uses QNetworkAccessManager loses Internet access through its Wi-Fi connection, then it fails to use the cellular link to access Internet.

Steps to reproduce:

1. Build attached minimal project
2. Make sure you have Wi-Fi connected to Internet AND cellular activated
3. Start app > click "ping" > you should see something downloaded
4. Disable Wi-Fi from the device settings
   1. Variant: switch to another Wi-Fi with no Internet access
5. Return to app > click "ping" > cannot access Internet despite cellular connection

Note: if you can't reproduce this issue, try to enable/disable the Wi-Fi a few times and retry. Restarting the device seems to momentarily fix the issue.

Note 2: if you start the app with Wi-Fi disabled, it can access Internet with cellular.

Android seems not affected by this.

Related issues:

• https://bugreports.qt.io/browse/QTBUG-60366
• https://bugreports.qt.io/browse/QTBUG-49751

The above-mentioned issues relate to the QNAM not restoring Internet access after Wi-Fi was disabled and then re-enabled. My issue is different: it's Qt not switching to cellular when there is no more Internet access through Wi-Fi.