I followed this
Everything is fine (not error during upgrade either). However, user's in the permission groups still shows domain\username instead of claim based. If i add a new user then it shows i:0#.w|domain\davidhassel01
Since it's a 2013 site so the web app is already claimed based. I can't read the SP groups using powershell script.
The SP 2010 is classic and i can't just change it to claims because it's production site.
Any idea on how to fix this issue?