my cookies are cleaned on every firefox exit. i tried using different firefox profile, without any add-ons. same thing.
I tried opera. it works with it.
Just another proof in a row that coinbase is a crappy site/exchange. I'll be sending my BTC from there promptly and closing the account.
thanks.

edit: it doesn't work in opera properly also. so basicaly now I have a fu**ing coinbase account with some BTC funds that I can't use cos of their shitty service.