Configuration warning: 'GD and/or Zip PHP extensions not found'

$modx->placeholders['config_display'] = 'none';

<?php
// turn it into an array for easier handling, 
//there are too many HTML tags and line endings to work directly with the error string
$errors = explode('Configuration warning', $modx->placeholders['config_check_results']);
// dig through the array for the GD and Zip warning
foreach($errors as $key=>$value) {
    if(strpos($value, 'GD and Zip') !==false) $gdkey = $key;
}
//drop the GD and Zip warning
unset($errors[$gdkey]);
// the first element will be the error list heading
if(count($errors)>1) {
        // put it back together
        $string = implode('Configuration warning', $errors);
        // replace the error message
        $modx->placeholders['config_check_results'] = $string;
} else {
        // no other errors, don't show the tab at all
        $modx->placeholders['config_display'] = 'none';
}
return;