JSFiddle - React, Tailwind, and code Playground

JavaScript

var xArray= ['link', 'block', 'hide', 'link', 'menu', 'block', 'content', 'link', 'footer', 'img', 'img', 'link', 'modal', 'button', 'form', 'input', 'button', 'input', 'link', 'toString', 'valueOf', 'button'];
var xNew=[];
var temp;

for(var i=0;i<=xArray.length-1;i++)
{
   if( xNew.indexOf(xArray[i]) === -1 )
   {
   xNew.push(xArray[i])    
   }
}

function occuranceOf(xStr)
{
    var xCount =0;
    for(var i=0; i<=xArray.length-1; i++)
    {
        if(xArray[i] === xStr)
            {
        xCount += 1;        
            }                 
    }
    
    return xCount;
}

for(var i=0;i<=xNew.length-1;i++)
{
    for(var j=i+1; j<=xNew.length-1; j++)
    {
        if(occuranceOf(xNew[i]) < occuranceOf(xNew[j]))
        {
            temp = xNew[i];
            xNew[i] = xNew[j];
            xNew[j] = temp;
        }
    }
}

alert(xNew);