diff --git a/wp-admin/css/wp-admin.css b/wp-admin/css/wp-admin.css
index 33e709b28e..fd829950e5 100644
--- a/wp-admin/css/wp-admin.css
+++ b/wp-admin/css/wp-admin.css
@@ -2993,6 +2993,17 @@ ul.cat-checklist {
 	float: left;
 }
 
+#lost-connection-notice .spinner {
+	display: block;
+	float: left;
+	margin: 0 5px 0 0;
+}
+
+.rtl #lost-connection-notice .spinner {
+	float: right;
+	margin: 0 0 0 5px;
+}
+
 #titlediv {
 	position: relative;
 	margin-bottom: 5px;
diff --git a/wp-admin/edit-form-advanced.php b/wp-admin/edit-form-advanced.php
index 9322f272b4..96ba2a96d6 100644
--- a/wp-admin/edit-form-advanced.php
+++ b/wp-admin/edit-form-advanced.php
@@ -313,7 +313,9 @@ if ( isset( $post_new_file ) && current_user_can( $post_type_object->cap->create
 <div id="message" class="updated"><p><?php echo $message; ?></p></div>
 <?php endif; ?>
 <div id="lost-connection-notice" class="error hidden">
-	<p><?php _e("You have lost your connection with the server, and saving has been disabled. This message will vanish once you've reconnected."); ?></p>
+	<p><span class="spinner"></span> <?php _e( '<strong>Connection lost.</strong> Saving has been disabled until you&#8217;re reconnected.' ); ?>
+	<span class="hide-if-no-sessionstorage"><?php _e( 'We&#8217;re backing up this post in your browser, just in case.' ); ?></span>
+	</p>
 </div>
 
 <form name="post" action="post.php" method="post" id="post"<?php do_action('post_edit_form_tag', $post); ?>>
diff --git a/wp-includes/js/autosave.js b/wp-includes/js/autosave.js
index c74f8404a1..e97c7bb5a8 100644
--- a/wp-includes/js/autosave.js
+++ b/wp-includes/js/autosave.js
@@ -144,7 +144,11 @@ jQuery(document).ready( function($) {
 	// When connection is lost, keep user from submitting changes.
 	$(document).on('heartbeat-connection-lost.autosave', function( e, error ) {
 		if ( 'timeout' === error ) {
-			$('#lost-connection-notice').show();
+			var notice = $('#lost-connection-notice');
+			if ( ! wp.autosave.local.hasStorage ) {
+				notice.find('.hide-if-no-sessionstorage').hide();
+			}
+			notice.show();
 			autosave_disable_buttons();
 		}
 	}).on('heartbeat-connection-restored.autosave', function() {