Paying eBay Fees Through PayPal Leaves PayPal Logged In
Checking when I paid for some non-eBay stuff, this did not happen.
So just a heads up when you pay through eBay using PayPal, make sure you are logged out of PayPal when you are finished. I don't know how long it stays open, but probably for whatever time the PayPal cookie is valid.
I only accidentally noticed this a couple of weeks ago. I can just imagine what could happen if you walked away from a computer with wide open access to your PayPal account.