If you are looking to add a custom default gravatar for your WordPress blog, you will need to open up your functions.php file and add this code to it. Please note that the code below is assuming that the image is placed in your theme’s images folder and called gravatar.png.
if ( !function_exists('fb_addgravatar') ) {
function fb_addgravatar( $avatar_defaults ) {
$myavatar = get_bloginfo('template_directory') . '/images/gravatar.png';
$avatar_defaults[$myavatar]='Custom';
return $avatar_defaults; }
add_filter('avatar_defaults', 'fb_addgravatar'); }
To utilize this feature, go into your WordPress dashboard under Settings > Discussion and you will see this at the bottom of the screen. The one that is shown is a custom default gravatar for the StudioPress site.
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