I find myself unable to comment on questions or answers on Stack Overflow today. My reputation is 53K, so it's not a problem with insufficient reputation.
Is something currently broken with the authorization / authentication system?
I was getting an error to the effect User lacks permission. Now I am getting a different error,
An error occured during comment submission
I was just now able to submit a comment. Hopefully the issue is fixed and not just transiently working.
It could not submit a second comment. It seems the issue remains.