iOS (but not Android) requests to Cloud Code (only) fail

I have an app that is fully working on Android, that is built on an Ionic, Cordova (frontend) and (Backend) framework.

Everything seems to work ok except for Cloud Code calls (and I can’t avoid them in a few scenarios where I’m dealing with the Installation data type). Any normal ajax call works, but POST calls to cloud code get stuck. An inspection of the network reveals that they never reach the server. Safari shows them as eternally pending.

I have a wildcard setting in config.xml, that works great on Android:

I tried tampering with it, allowing subdomains, being more specific and allowing “”, but to no avail.