That's not a very useful option
How many of us still start up a browser, use it, and then close the browser? What is this, 1998? I open Firefox immediately after rebooting my PC, and leave it running for a couple months on average with a couple dozen tabs opened across a half dozen windows. I only shut it down because I want to install patches that will require a reboot, or have a power outage longer than the hour my UPS will last.
It would be far more useful to have an option to clear cookies from a site when all tabs pointing at that site are closed. If I'm going to do a google search (I usually use DDG, but let's say I can't find what I'm looking for there) I will open a tab or window for it, then visit one or more links from that search to find what I'm looking for, then close those tabs. It would be awesome if those cookies were removed immediately, not sticking around for weeks and weeks when they aren't needed or wanted. Getting rid of the Facebook, doubleclick and other useless third party cookies related to those sites would make it even sweeter.
Sure, I could get into the habit of reopening my browser daily I suppose, but why should I do that when the browser could take it for me? And why should I wait to have those cookies cleared, when they could be immediately cleared when a tab is closed?
Biting the hand that feeds IT
