I have an email template to send on a shipping notification that includes a shipping tracking number as below and I need to clear all the spaces from href using plain javascript:

<a class="press-bt" id="clearSpace" href="https://www.royalmail.com/track-your-item?trackNumber=JX12 0008 990 90GB">TRACK</a>

I can get it right using jQuery but not using Javascript

I am trying to do it this way:

window.onload = function() {
    var str = document.getElementById("mylink");
    document.write( str.replaceAll("\\s+","") );
});

Working code using jQuery:

$(document).ready(function() {
    $('a').attr('href', function (_, val) {
        return val.replace(/\s/g, '');
    });
});

Target the element by its id, grab the href attribute, and set it again by removing the spaces.

var link = document.getElementById("mylink");
var href = link.getAttribute('href');
link.setAttribute('href', href.replace(/\s/g, ''));

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