JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://code.jquery.com/ui/1.8.24/themes/base/jquery-ui.css">
Date1: <input type="text" id="datepicker1" value="08.09.2005">
Next input: <input><br>
Date2: <input type="text" id="datepicker2" value=""><br>
Date3: <input type="text" id="datepicker3" value="">

JavaScript

jQuery.fn.enablePlusMinusInDatePicker = function(today){
    
    if (!today) {
        if ($(this).val() !== '') {
            today = $(this).val();
        }
        else {
            today = new Date();
        }
    }
    
    function changeDay(obj, plus){
        if (obj.val()){
            var date = obj.datepicker("getDate");
            date.setDate(date.getDate() + (plus? 1: -1));
            obj.datepicker("setDate", date);
        }    
    }
        
    this.keypress(function(e){
        switch (String.fromCharCode(e.charCode || e.keyCode)){
            case "+":
                changeDay($(this), true);
                e.preventDefault();
                break;
            case "-":
                changeDay($(this), false);
                e.preventDefault();
                break;
            case "h":
            case "H":
                $(this).datepicker("setDate", today);
                e.preventDefault();
                break;
        }
    });
    
    return this;
};
    
$( "#datepicker1" )
    .datepicker({dateFormat: "dd.mm.yy"})
    .enablePlusMinusInDatePicker();

$( "#datepicker2" )
    .datepicker({dateFormat: "dd.mm.yy"})
    .enablePlusMinusInDatePicker('31.12.1950');

$( "#datepicker3" )
    .datepicker({dateFormat: "dd.mm.yy"})
    .enablePlusMinusInDatePicker();