Show user favicon in user blog loop

I used a snippet from one of your colleagues, to create a list of blogs for a user, and I want to add the favicon from the site to the list...

The snippet I used is here: https://www.+++.me/blog/tech/wordpress/list-blogs-subsites-wordpress-multisite-user/

and I added this to the code just after the opening a tag in the

  • :

    if (has_site_icon()) {
    echo '<img src="'.$user_blog->get_site_icon_url.'" alt="'.$user_blog->blogname.'"/> ';
    } else {
    echo '<img src="http://placehold.it/512x512"/>';
    }

    But it doesn't work, it outputs the img tag with src=(unknown). Is there anyway I can make this work? Any help is appreciated.
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