diff --git a/wp-admin/includes/theme.php b/wp-admin/includes/theme.php
index dda79cbd48..c7a8ce5768 100644
--- a/wp-admin/includes/theme.php
+++ b/wp-admin/includes/theme.php
@@ -163,18 +163,20 @@ function get_theme_update_available( $theme ) {
 		$theme_name = $theme->display('Name');
 		$details_url = add_query_arg(array('TB_iframe' => 'true', 'width' => 1024, 'height' => 800), $update['url']); //Theme browser inside WP? replace this, Also, theme preview JS will override this on the available list.
 		$update_url = wp_nonce_url( admin_url( 'update.php?action=upgrade-theme&theme=' . urlencode( $stylesheet ) ), 'upgrade-theme_' . $stylesheet );
-		$update_onclick = 'onclick="if ( confirm(\'' . esc_js( __("Updating this theme will lose any customizations you have made. 'Cancel' to stop, 'OK' to update.") ) . '\') ) {return true;}return false;"';
 
 		if ( !is_multisite() ) {
 			if ( ! current_user_can('update_themes') ) {
-				$html = sprintf( '<p><strong>' . __( 'There is a new version of %1$s available. <a href="%2$s" class="thickbox" title="%3$s">View version %4$s details</a>.' ) . '</strong></p>',
-					$theme_name, esc_url( $details_url ), esc_attr( $theme['Name'] ), $update['new_version'] );
+				/* translators: 1: theme name, 2: theme details URL, 3: theme version number */
+				$html = sprintf( '<p><strong>' . __( 'There is a new version of %1$s available. <a href="%2$s" class="thickbox">View version %3$s details</a>.' ) . '</strong></p>',
+					$theme_name, esc_url( $details_url ), $update['new_version'] );
 			} elseif ( empty( $update['package'] ) ) {
-				$html = sprintf( '<p><strong>' . __( 'There is a new version of %1$s available. <a href="%2$s" class="thickbox" title="%3$s">View version %4$s details</a>. <em>Automatic update is unavailable for this theme.</em>' ) . '</strong></p>',
-					$theme_name, esc_url( $details_url ), esc_attr( $theme['Name'] ), $update['new_version'] );
+				/* translators: 1: theme name, 2: theme details URL, 3: theme version number */
+				$html = sprintf( '<p><strong>' . __( 'There is a new version of %1$s available. <a href="%2$s" class="thickbox">View version %3$s details</a>. <em>Automatic update is unavailable for this theme.</em>' ) . '</strong></p>',
+					$theme_name, esc_url( $details_url ), $update['new_version'] );
 			} else {
-				$html = sprintf( '<p><strong>' . __( 'There is a new version of %1$s available. <a href="%2$s" class="thickbox" title="%3$s">View version %4$s details</a> or <a href="%5$s">update now</a>.' ) . '</strong></p>',
-					$theme_name, esc_url( $details_url ), esc_attr( $theme['Name'] ), $update['new_version'], $update_url, $update_onclick );
+				/* translators: 1: theme name, 2: theme details URL, 3: theme version number, 4: theme update URL */
+				$html = sprintf( '<p><strong>' . __( 'There is a new version of %1$s available. <a href="%2$s" class="thickbox">View version %3$s details</a> or <a href="%4$s">update now</a>.' ) . '</strong></p>',
+					$theme_name, esc_url( $details_url ), $update['new_version'], $update_url );
 			}
 		}
 	}
diff --git a/wp-includes/version.php b/wp-includes/version.php
index d8c002adf9..c1dff0d82e 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.5-alpha-36014';
+$wp_version = '4.5-alpha-36015';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.