Excuse my French, but what does that have to do with anything? The issue at hand is about Facebook not respecting your request to log out of their service. "Lo

Excuse my French, but what does that have to do with anything? The issue at hand is about Facebook not respecting your request to log out of their service. "Log out" means "I'm going away. Do not assume anyone on this computer is me anymore." Facebook deliberately choose to ignore this convention, and continue to track users using various methods in order to gather more information for their purposes. What Facebook should have done was delete all Facebook cookies - end of story. How that is related to the pros and cons of HTTP is beyond me.