iOS - Unable to save password in HTML form despite autocomplete attribute

I am working on a Cordova App and I followed the [Apple guidelines and added to autocomplete attributes to my HTML login form](https://developer.apple.com/documentation/security/password_autofill/enabling_password_autofill_on_an_html_input_element) to ask users whether they want to save their credentials when they try to sign up.

On Android the popup correctly appears and I'm able to pick my stored credentials the next time I try to log in. **That's not the case on iOS though**.

The first thing that comes to my mind that could prevent the webview to associate passwords and domains for iOS is the fact that I use a custom domain for the latter (eg. iosapp://).

I am not allowed to change the custom domain in use, is there a way to still let the App prompt the user to save their credentials?

-----

This issue can be reproduced in this way:
1. Add the [plugin cordova-plugin-ionic-webview][1] to a Cordova App
2. Add `` to your config.xml to specify a custom hostname for your app (the default one ionic:// I think would have the same issue too)
3. onDeviceReady redirect to my PoC (that works in all other browsers):

```
window.location.href = 'https://gabriele-sacchi.github.io/pocs/biometric';
```

**Expected result**: after you sign up with random credentials it should ask you whether you want to save your credentials
**Actual result**: on iOS the popup does not appear

Thanks

_{([Stacko question](https://stackoverflow.com/questions/62870033/cordova-plugin-ionic-webview-unable-to-save-password-in-html-form-despite-auto))}

_{PoC working in Android Cordova:}

[1]: https://github.com/ionic-team/cordova-plugin-ionic-webview