QR Code stripping multiple consecutive spaces from the entered code

I found this bug

Attempting to create a QR code with the value ETEX14 0001 (where there are 6 consecutive spaces) - the extra spaces are getting stripped and the resulting code is ETEX14 0001 - I have searched for where this is happening and not been able to find it or find any work-around. I have checked that I am able to read a QR code with the spaces correctly encoded by using a different tool to generate the QR code so I am reasonably sure the code is being "minified" somewhere in mPDF and excess spaces stripped out. I have not been able to find any option or configuration change that will stop this happening despite searching for several hours and attempting many configuration changes. I apologize if this is a configuration issue and not a bug, but I have not been able to get this working.

This is mPDF and PHP version and environment (server/fpm/cli etc) I am using

Using mpdf/mpdf V8.0.10, mpdf/qrcode V1.2.0 running under PHP 7.4 on Apache V2.4.41

This is the PHP code snippet I use

<?php

    // Require composer autoload - create $mpdf object
    require_once $_SERVER['DOCUMENT_ROOT'].'/vendor/autoload.php';
    $mpdf = new \Mpdf\Mpdf([
        'format' => 'A4-P',
        'mode' => 'utf-8',
        'margin_left' => 0,
        'margin_right' => 0,
        'margin_top' => 0,
        'margin_bottom' => 0,
        'margin_header' => 0,
        'margin_footer' => 0,
        'nonPrintMargin' => 4
    ]);  //MPDF8

//Create HTML page in variable $html...(not shown)

$Location = 'EX14';
$BarcodeLocation = 'ET' . str_pad($Location, 10, " ", STR_PAD_RIGHT) . '0001';
$html .= "<barcode code=\"$BarcodeLocation\" type=\"QR\" class=\"barcode\" size=\"0.3\" error=\"M\" disableborder=\"1\" />\n";

//much later...
$mpdf->WriteHTML(trim($html),\Mpdf\HTMLParserMode::DEFAULT_MODE);
$mpdf->Output("Int_Doc_A4_Labels.pdf", "I");

This is the HTML/CSS code snippet I use

All is above...

mpdf / qrcode