'draft is being edited in another window'

Just got this pop up message when I was submitting a reply to a post.

‘Draft is being edited in another window - please refresh page’ or something like this. however I got heavily confused given I had no other windows open, at least on my Mac.

Checking my phone I did have dev forum open but as far as im concerned no post draft.

Just checking to see if this a message i should be concerned about since it could mean someone is in my account.


I had this the other day, this just seems like a minor bug.