Hide empty fields in YITH Woocommerce Product Plugin

I created a copy of YITH Woocommerce Compare compare.php and added the following code before <tr in line 116)

<?php
$show_field = 0;
foreach( $products as $i => $product ) :
    if( ! empty( $product->fields[$field] ) ) {
        $show_field = 1;
    }
endforeach;

if( $show_field == 1 ) : ?>

and put <?php
$show_field = 0;
foreach( $products as $i => $product ) :
if( ! empty( $product->fields[$field] ) ) {
$show_field = 1;
}
endforeach;

if( $show_field == 1 ) : ?>
after </tr> in line 143

It does not hide blank fields in the comparison.

I thought the above code would work? I cannot see why it doesn’t.