I’m on the latest version and I could not change the slug either at the bottom of the page or in the Publishing section even when all other plugins were deactivated.
However, Admin Columns Pro did let me change the slug. Thanks @supremebeing88
Don’t know if this is related, and maybe I should make a separate post, but more often than not, when I’m editing a template normally and click update, the update button says saved briefly, then back to update. However, if try to close that template without making any further changes, I get the message:
Leave site?
Changes you made may not be saved.
I’m using the current version of Chrome.