JSFiddle - React, Tailwind, and code Playground

HTML

<a href='#home'>First</a>

<a href='#about'>Second</a>

<a href='notHash'>Not Hashed</a>

JavaScript

$('a[href^="#"]').each(function (i, el) {
    el.href = "http://www.example.com/pageslug" + el.hash;
});