Ok, let me explain.
I have InAppBrowser integrated into my Unity iOS app for opening any/all URLs in an internal browser instead of sending the user off to an external browser app. Now the URLs could be either http:// or https:// based on the website the Url belongs to and I have couple of http:// based website URLs and a couple of https:// based website URLs.
Now in the player settings of my Unity iOS app if I disable ‘Allow downloads over HTTP (nonsecure)’ checkbox(for publishing on App Store) and build the app, http:// based URLs are not opening in the InAppBrowser. The InAppBrowser panel opens but the webpage does not load and loader stays on forever.
To reproduce this issue, simply open the ExampleScene from InAppBrowser asset in a Unity iOS project and set the URL as ‘https://www.kokosoft.pl/’ in the URL box in the BrowserOpener component. Then disable the ‘Allow downloads over HTTP (nonsecure)’ checkbox in the iOS player settings and build it. The webpage at the url ‘https://www.kokosoft.pl/’ will not load in the InAppBrowser.
Please try this once and let me know if you are able to reproduce this at your end.