safari 8.0.3 Username/Password autofill not working

This morning I was using username/password autofill in Safari 8.0.3 successfully but suddenly (in the same session of Safari) it suddenly stopped working! I hover over or click on the username field of any website and nothing happens. No autofill prompts

I'm using:-

OS X Yosemite v 10.10.2; iMac 27" late 2013

Keychain Access v9.0 (55161)

Safari 8.0.3 (10600.3.18)

I have:-

- tried to verify and repair keychain but no problems reported

- found that Autofill user names and passwords is checked in Safari>preferences>passwords. But, the table below the setting is empty

- been able to autofill credit card details without any problems

- Keychain is enabled in my iCloud settings

- successfully used autofill in Safari on my iPhone (iOS 8.1.3)

- noticed that I'm still prompted to save a username/password for a new site when using Safari 8.0.3 on my desktop

- deleted the Safari Forms Autofill entry in Keychain Access: closed down Keychain and Safari, rebooted machine. But, no success.

Can anyone offer any advice please?

Thank you.

Andy