JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js">

</script>
Before:
<table class="unmodified_table" border="1">       
    <tr><td>1</td><td>22</td></tr>
    <tr><td>2</td><td >22</td></tr>
    <tr><td>3</td><td >88</td></tr>
    <tr><td>4</td><td>22</td></tr>
    <tr><td>5</td><td >22</td></tr>
    <tr><td>5</td><td >22</td></tr>
    <tr><td>6</td><td>3</td></tr>
    <tr><td>7</td><td >44</td></tr>
    <tr><td>8</td><td >55</td></tr>
</table>
<br /> </br>

After:
<table class="modified_table" border="1">  
    <tr><td>1</td><td>22</td></tr>
    <tr><td>2</td><td >22</td></tr>
    <tr><td>3</td><td >88</td></tr>
    <tr><td>4</td><td>22</td></tr>
    <tr><td>5</td><td >22</td></tr>
    <tr><td>5</td><td >22</td></tr>
    <tr><td>6</td><td>3</td></tr>
    <tr><td>7</td><td >44</td></tr>
    <tr><td>8</td><td >55</td></tr>
</table>

JavaScript

var column2 = $('.modified_table td:nth-child(2)');


modifyTableRowspan(column2);



//the function
function modifyTableRowspan(column) {

        var prevText = "";
        var counter = 0;

        column.each(function (index) {


            var textValue = $(this).text();

            if (index === 0) {
                prevText = textValue; 
            }
            
            if (textValue !== prevText || index === column.length - 1) {

                var first = index - counter;

                if (index === column.length - 1) {
                    counter = counter + 1;
                }

                column.eq(first).attr('rowspan', counter);


                if (index === column.length - 1)
                {
                    for (var j = index; j > first; j--) {
                        column.eq(j).remove();
                    }
                }

                else {

                    for (var i = index - 1; i > first; i--) {
                        column.eq(i).remove();
                    }
                }

                prevText = textValue;
                counter = 0;
            }

            counter++;

        });

    }