I downloaded from this site the "Paypal Verified Logo" sidebox.
When you click on the logo you arrive on the paypal site for logging in with next in my location bar:

https://www.paypal.com/verified/[email protected]

My question is if that is not too unsafe with your email address in the location bar just above the login form of the paypal site. I'm not certain if it was a visitor of my shop but I got once a request from paypal to make my password safer because there had been an attack on my account they said.