On the Nationwide UK online banking website certain transactions take an age on Firefox 18 (and all previous versions that I remember) which happen without delay on Chrome. The transactions are usually transfers between accounts which have several steps over a series of pages. Submitting each page appears to happen swiftly but in fact a status message remains on the new page saying 'Waiting for onlinebanking.nationwide.co.uk'. This typically remains for 20 seconds to a minute. If I don't notice this and submit the next page before it goes away the whole transaction locks up and I have to start again.
Windows XP Home SP 3, 4GB RAM Intel 2GHz DualCore.
The problem is 100% reproducable on my system. I've called Nationwide and they say they can't fix it. It always works fine with no delays at all on Chrome. I've tried with Firefox in safe mode and get the same problem.