If you want to stop people from pinning the Gravatar image from your Author box or comments, you can add the following code to your WordPress functions.php file.
If you do not know how to access your functions.php see this post for instructions.
if (have_comments()) {
$alt = get_comment_author();
}
else {
$alt = get_the_author_meta('display_name');
}
$wpbaGravatar = str_replace('alt=\'\'', 'alt=\'Avatar for ' . $alt . '\' title=\'Gravatar for ' . $alt . '\' data-pin-nopin=\'true\'', $wpbaGravatar);
return $wpbaGravatar;
}
add_filter('get_avatar', 'wpba_gravatar_nopin');
The code above is modified from this post here to add the alt text to your gravatar on Crunchify, modified above to add the nopin option to your author and comment gravatar images.
Note – if someone uses the Tailwind extension, enters your URL on Pinterest directly or another method to pin your post the images may still be pinnable.