Actually it can handle the email part also. You just have to add the site URL to Site Preferences in the extension's settings and enable Username-only detection

Actually it can handle the email part also. You just have to add the site URL to Site Preferences in the extension's settings and enable Username-only detection. It's a necessary extra step so the credentials wouldn't be filled to search fields or to other single input fields. It's quite hard to detect if an input field is actually a username field.