var target = new Date(2019,0,1);
var date = new Date();
if (target.getFullYear() <= date.getFullYear()
&& target.getMonth() <= date.getMonth()
&& target.getDate() <= date.getDate()){
$(".window").css("display", "block");
}
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<!--[if (gt IE 9)|!(IE)]><!--> <html> <!--<![endif]-->.ie9 .button {
disblay:block;
}