Here is my answer when you want to revive it and start to fade in a couple of seconds. I used opacity because in the first place I did not want to completely disappear, and secondly, it does not return and does not amplify after many scrolls.
$(window).scroll(function () { var elem = $('div'); setTimeout(function() { elem.css({"opacity":"0.2","transition":"2s"}); },4000); elem.css({"opacity":"1","transition":"1s"}); });
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