Ticket #22329: 22329.2.patch

src/wp-includes/pluggable.php

@@ -2142 +2142 @@
                 $args = array();
         }
 
-        $args['size']    = $size;
+        $args['size']    = (int) $size;
         $args['default'] = $default;
         $args['alt']     = $alt;
 
@@ -2170 +2170 @@
                 return false;
         }
 
+        $url2x = get_avatar_url( $id_or_email, array_merge( $args, array( 'size' => $args['size'] * 2 ) ) );
+
         $args = get_avatar_data( $id_or_email, $args );
 
         $url = $args['url'];
@@ -2193 +2195 @@
         }
 
         $avatar = sprintf(
-                "<img alt='%s' src='%s' class='%s' height='%d' width='%d' />",
+                "<img alt='%s' src='%s' srcset='%s' class='%s' height='%d' width='%d' />",
                 esc_attr( $args['alt'] ),
                 esc_url( $url ),
+                esc_attr( "$url 1x, $url2x 2x" ),
                 esc_attr( join( ' ', $class ) ),
                 (int) $args['size'],
                 (int) $args['size']