Ticket #34951: 34951.patch

src/wp-includes/css/wp-auth-check.css

@@ -48 +48 @@
 }
 
 #wp-auth-check-wrap #wp-auth-check-form {
-        background: url(../images/spinner-2x.gif) no-repeat center center;
-        -webkit-background-size: 16px 16px;
-        background-size: 16px 16px;
         height: 100%;
+        position: relative;
         overflow: auto;
         -webkit-overflow-scrolling: touch;
 }
 
+#wp-auth-check-form.loading:before {
+        content: "";
+        display: block;
+        width: 20px;
+        height: 20px;
+        position: absolute;
+        left: 50%;
+        top: 50%;
+        margin: -10px 0 0 -10px;
+        background: url(../images/spinner.gif) no-repeat center;
+        -webkit-background-size: 20px 20px;
+        background-size: 20px 20px;
+        -webkit-transform: translateZ(0);
+        transform: translateZ(0);
+}
+
+@media print,
+  (-webkit-min-device-pixel-ratio: 1.25),
+  (min-resolution: 120dpi) {
+
+        #wp-auth-check-form.loading:before {
+                background-image: url(../images/spinner-2x.gif);
+        }
+
+}
+
 #wp-auth-check-wrap #wp-auth-check-form iframe {
         height: 98%; /* Scrollbar fix */
         width: 100%;

src/wp-includes/functions.php

@@ -4934 +4934 @@
 
         if ( $same_domain ) {
                 ?>
-                <div id="wp-auth-check-form" data-src="<?php echo esc_url( add_query_arg( array( 'interim-login' => 1 ), $login_url ) ); ?>"></div>
+                <div id="wp-auth-check-form" class="loading" data-src="<?php echo esc_url( add_query_arg( array( 'interim-login' => 1 ), $login_url ) ); ?>"></div>
                 <?php
         }
 

src/wp-includes/js/wp-auth-check.js

@@ -20 +20 @@
                                 var height, body;
 
                                 loaded = true;
+                                // Remove the spinner to avoid unnecessary CPU/GPU usage.
+                                form.removeClass( 'loading' );
 
                                 try {
                                         body = $(this).contents().find('body');
@@ -46 +48 @@
                                 }
                         }).attr( 'src', form.data('src') );
 
-                        $('#wp-auth-check-form').append( frame );
+                        form.append( frame );
                 }
 
                 $( 'body' ).addClass( 'modal-open' );