MFA not working after enabling Next Experience in Utah

[Chris Dea1]

Hi there,

We're currently on Utah and we are planning to enabling Next Experience before we upgrade to Vancouver in the coming weeks.  We have role-based MFA setup for users with admin role.  I enabled Next Experience in our test instance by setting both the system properties glide.ui.polaris.experience to "true" and glide.ui.polaris.on_off_user_pref_enabled to "true".  I logged out and then attempted to login as an admin and that is where the issue is...

...When I login as an admin, I enter the login and password (screenshot 1) and then I am presented with the "Verify your identity" screen which now has Polaris theme (screenshot 2), I enter in my MFA code, and then get taken right back to a login screen (screenshot 3).  (I logged in as an admin into a different Dev instance where Next Experience is not enabled and I am able to login with MFA normally._   Besides the MFA screen being Polaris themed I also noticed I get taken to welcome.do after entering the MFA code; however in the Dev instance where login with MFA works (without Next Experience), I get taken to sp?id=landing page instead.

Has anyone else encountered this issue after enabling Next Experience?  Do I need to update a script/script include after enabling Next Experience in order for login with MFA to work?  

I am locked out of our test instance right now so I am asssuming I need clone down prod to test to overwrite the changes but hopefully someone can tell me how to avoid and fix this issue.

Thanks,

Chris