I need to replace characters inside specific tag using javascript when page loads. I have a big list of characters to be replaced. so it will be fast and should work with major browsers. 
example:-

```
<p> The quick brown fox jumps over the lazy dog </p>

```

will need to looks like

```
<p> h=f t)ujh lk.,h ghy tfbm' bhjf ghy {>ht Frt </p>

```

Thanks!