I noticed this issue while testing our web application under Chrome. While testing the application I need to clear all browser data since the beginning of time, login and logout of our application. We do this over and over, which makes it easy to spot problems like this.
Upon logging into our application for the first time the 1password chrome extension problems you will be prompted to create or update a new entry within 1password. Simultaneously Chrome will offer to remember this password for you.
If you avoid interacting with either of these dialogs, and instead focus on the freshly loaded web application you will discover that single clicks will not register while double clicks will incorrectly register as single clicks. Interacting with the browser is effectively broken at this point, even if you switch between tabs.
The issue will resolve if you unfocus chrome (click on the desktop, another application, etc).
The issue only appears to affect Chrome.
1Password Version: 6.3.1
Extension Version: 22.214.171.124
OS Version: 10.11.5
Sync Type: iCloud