1Password support in FireFox under Windows is abysmal. There are intermittent, but frequent problems. They are -
1) clicking on the 1Password icon on FireFox menu does not always bring up 1Password master password dialogue. Restarting FireFox usually resolves this.
2) after clicking on the 'login' selection on drop down menu a list of sites is presented, but selecting a site results in redisplaying the 1Password first level 'login' menu.
3) there's something that goes wrong when filling in the user id, in that the web sites sometimes see the id as invalid. Turning off auto-logon helps somewhat but not entirely.
Also, why, if I have already entered my password on 1Password under my browser, do I then have to renter it if I open 1Password desktop? And vice versa. It isn't like there are two different passwords. Once should be enough for both the browser interface and the desktop app.
Also, if I have entered a password on the desktop why am I prompted to renter it if I do a wi-if sync from my iOS device. It isn't like there are two different passwords. I've already opened the desktop and entered my password prior to the wi-if sync.
Recently, I've started test running 1Password on my Mac. Some of these problems don't seem to be present under 1Password 5. Maybe 1Password 5 should be on Windows, also.