"Read More" for long product desriptions

By default WC doesn′t seems to support “Read more” tag in product description. I almost finished a workaround for that limitation. I add in function.php of storefront-child theme (in my case) this undocumented pluggable WC function:

function woocommerce_product_description_tab() {
    global $post;
    $heading = esc_html( apply_filters( 'woocommerce_product_description_heading', __( 'Product Description', 'woocommerce' ) ) );
    if ( $heading ):
      echo "<h2>$heading</h2>";
    endif;

    global $more;
    $more = 0;

    the_content(__('(more...)'));
}

But still have a problem, content below “more” got stripped (not even in source code) and still don′t know why?

Using WP4.1.1. + WC2.3.5

I realized that the_content function (which WC also uses) doesn’t allow “Read more” to work if it’s outside the loop. I resolved it using an spoiler plugin to partially hide content.

I have been searching and found this which is very useful for me:

<details>
<summary>read more…</summary>
<p>If your browser supports this element, it should allow you to expand and collapse these details.</p></details>