I'm researching if there is a way that window.onunload event gets fired on inactive tabs in Chrome browser.

The idea is that if i keep a page's tab active (let's say its index is 3), the event will fire if I (for example) close the browser. However, if i am navigating on some other page(s), the onUnload event on tab-index 3 (my page) will not fire (as it is not the active tab)

To my opinion, I would have thought that onunload gets fired for all tabs in the browser... but as to my tests... it only fires on the active-tab.

Is there any way to register a listener to detect if the browser closes even if (my) site is not lucky to sit in the "active" tab?