FWIW and to confirm. I have my regular browsers permanently logged into Smugmug, and it allows me to leave a comment. It know it's me 'cos my face pops up. I didn't leave a comment because I had nothing to sayI don't think it should. The old Smugmug never did. Anyone could leave a comment.
If I use Explorer, which is not logged in, then it does ask me to before leaving a comment.