check element exist in jquery

JavaScript
if ($('.element').length) {
  // there is at least one element matching the selector
}$(function() {
    var $button = $(".the_button");
    alert (isStale($button));
    $button.remove();
    alert (isStale($button));
});
    
function isStale($elem)
{
    return $elem.closest("body").length > 0;
};
Source

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