We’re getting a similar issue in iOS and have no problem loading the iframe content in Android builds. The Safari dev tools report 403 when attempting to load the iframe src. We are using Gigya’s WebSDK RaaS which dynamically creates iframes to load their login / auth experience. We’re tried Gigya’s Cordova plugin but I believe we have to create an ionic-native wrapper around it (https://github.com/ionic-team/ionic-native/blob/3e0b0750d851fab8e6af189c8f4aafa091402f4e/DEVELOPER.md)… so we’re hoping to get their WebSDK RaaS working with iOS to get our POC moving along.
Thankfully we can get what we need by directly using Gigya’s REST API. There’s no swagger, but it is documented, so much more lightweight to use and to drop a music adage, “less is more.”