Action when browser back() or JS history.back()

"popstate"
IN THIS ARTICLE
General info
Properties
Browser compatibility
Example
Related Events
The popstate event is fired when the active history entry changes. If the history entry being activated was created by a call to history.pushState() or was affected by a call to history.replaceState(), the popstate event's state property contains a copy of the history entry's state object.

Note that just calling history.pushState() or history.replaceState() won't trigger a popstate event. The popstate event is only triggered by doing a browser action such as a click on the back button (or calling history.back() in JavaScript).

Browsers tend to handle the popstate event differently on page load. Chrome (prior to v34) and Safari always emit a popstate event on page load, but Firefox doesn't.

$(window).on("popstate", function(){
    alert(1);
});