I wish I could copy individual login items directly from the 1P button in a browser, instead of making several trip back & forth to the 1Password application.
This would help with login pages where 1Password has problems.
It would also keep me from having to retype the master password in the application while the 1P session is still open in the browser.
Speaking of incompatible pages, I have one login where 1P refuses to apply the login items in the text boxes (myPogoplug.com) - I already made a post about this particular one.
I also have a few other login pages where 1P puts items in the wrong boxes, notably those pages that have separate login fields for existing user (sign in), and for new user (sign up), and 1password puts the data in the "New user" signup fields. While I can copy/paste and move the Username within the page, I cannot do so for the dotted-out password.
The feature I mention here would be a time saver!