Success! Thanks Andrew Ozz. I was having the same problem seeing the full visual editor too, and nothing I did with my theme or plugins made any difference.
In the end I just deleted the wp-includes/js directory & uploaded a new copy via FTP. Everything is working fine now… phew.
hmm, clearing all cookies with the word “wordpress” in them fixed it straight away (Safari).
NB: this is for when you get the prompt “please log in again”, but not the prompt “Error: incorrect name or password”
