Removing(replacing) avtar in comments.php with some other HTML arrangements

Question

 <ol class="comment-list">
            <?php
                wp_list_comments( array(
                    'style'       => 'ol',
                    'short_ping'  => true,
                    'avatar_size' => 34,
                ) );
            ?>
        </ol><!-- .comment-list -->

This is controlling the avatar size →

'avatar_size' => 34, →

I want to replace this with an arrangement where inside a square box(background) I will have First letter of the name in the absence of an avatar. How can this be accomplished?

Answer 1

Use the get_avatar filter and develop a function to return whatever avatar you want.