I'm having a similar problem to the one described here viewtopic.php?f=12&t=273225. Every time I try to login to usps.com, first using the autofill using the LP extension will not work even if I right click on the icon on the login boxes for user name and password and second I get an error message from the site saying either the username or password is incorrect. They are correct and I am using the latest version of LP and Opera. Upon inspection of my extensions, I found that the Opera extension for Lastpass was definitely the culprit. However, once I copied and pasted both user name and password from my vault, I was able to login. What is stranger still, is that this problem does not occur in the Firefox extension of LP.