So, I managed to lock myself out of the admin (again), but used my brain and got myself back into the admin panel. (Ran the setup again and created a new admin account)
For the silly people like me who do things without thinking, can we add a check to make sure that there is always 1 admin in the system group for admin. 
Much appreciated.
How did you remove yourself as the admin? I thought we didn't allow that.
@baris Go into Groups, then edit the admin system group, remove yourself from that group. Refreshing or clicking anything in admin 403s, and the account is now a normal user.
Sounds like a regression. I specifically forbade the admin group (and registered users group) from being edited from the ACP, but it seems like Baris re-enabled it so that icons could be set?
I could be completely off the mark here though 
@julian Good timing then.
I added some checks so you can't remove yourself or the last admin. https://github.com/NodeBB/NodeBB/commit/07275b5fc42956f68c18895af963ea1b477d6708
