I'm having an issue with 1Password 5 on Yosemite when I use it to fill my password for my Google Drive account. I have several Drive accounts that I switch between on a regular basis. Google knows which one I'm trying to use based on the document I attempt to access from a bookmark, and it auto-fills my username. However, 1Password doesn't pick up on this and will always fill in the alphabetically first login details I've saved. This is frustrating because Google is boneheaded and will accept that password and log me into that other account, causing me to have to log out and go through Google's whole clunky switch process again.
So, maybe more clearly this way: