Web Browser in Android 9 vs Android 10

I’m currently running my expo app (development mode) from two phones, one with Android 9 (A9) and one with Android 10 (A10). In my app I utilize the Web Browser, through Expo’s AuthSession to login through Instagram. On A10, everything works perfectly. It opens a modal, shows the correct login form, and after logging in it redirects back to the app.

A9 however is completely different. It opens up a new tab rather than a modal, causes Instagram to respond with an error ONLY on Chrome (works for incognito, Opera, etc), and after logging in it fails to redirect back to the app. (redirects to the correct expo url but expo seems to fail to redirect back to the app).

Is this normal, and how can I fix it so it works on older versions of Android? I’m assuming it has to do with my app.json config but I have no idea how.