JSFiddle - React, Tailwind, and code Playground

JavaScript

var x1,x2,y1,y2;
var selected = false;
document.onmousedown = function(e){
    if(e.which == 3 && selected) //right click and already selected
    {
        if( ((e.clientX > x1 && e.clientX < x2) ||
            (e.clientX < x1 && e.clientX > x2)) &&
            ((e.clientY > y1 && e.clientY < y2) ||
             (e.clientY > y1 && e.clientY < y2))){
            alert("in selected area !! ");
        }
           
    }else{     
        x1 = e.clientX;
        y1 = e.clientY;
        selected = false;
    }
}

document.onmouseup = function(e){
    x2 = e.clientX;
    y2 = e.clientY;
    selected = true;
}