InAppBrowser issues with SSO

I have a Capacitor project which requires SSO login from an external Federation web page.

I am able to display the login page successfully using the InAppBrowser plugin (I have experimented with the capacitor plugin as well as the “awesome” cordova plugin).

My problem is that when I press the login button on our test ADFS server, the page just refreshes. I don’t believe the login call is ever executed.

Note that if I try this with an external browser on the phone it works fine. Also if I try other API links on the in-app browser, that works fine too.

Is there any reason why SSO would not work within an InAppBrowser?

Should I try the Cordova plugin (rather than “awesome” plugin?). I could try the capacitor plugin again, but it does not seem to be as feature-rich on callbacks.