diff --git a/wp-admin/includes/theme.php b/wp-admin/includes/theme.php
index 4024b395f4..a8c1fc0d50 100644
--- a/wp-admin/includes/theme.php
+++ b/wp-admin/includes/theme.php
@@ -511,6 +511,8 @@ function wp_prepare_themes_for_js( $themes = null ) {
  * @since 4.2.0
  */
 function customize_themes_print_templates() {
+	$preview_url = esc_url( add_query_arg( 'theme', '__THEME__' ) ); // Token because esc_url() strips curly braces.
+	$preview_url = str_replace( '__THEME__', '{{ data.id }}', $preview_url );
 	?>
 	<script type="text/html" id="tmpl-customize-themes-details-view">
 		<div class="theme-backdrop"></div>
@@ -550,7 +552,7 @@ function customize_themes_print_templates() {
 			<# if ( ! data.active ) { #>
 				<div class="theme-actions">
 					<div class="inactive-theme">
-						<a href="<?php echo add_query_arg( 'theme', '{{ data.id }}' ); ?>" target="_top" class="button button-primary"><?php _e( 'Live Preview' ); ?></a>
+						<a href="<?php echo $preview_url; ?>" target="_top" class="button button-primary"><?php _e( 'Live Preview' ); ?></a>
 					</div>
 				</div>
 			<# } #>
diff --git a/wp-includes/class-wp-customize-control.php b/wp-includes/class-wp-customize-control.php
index 024f16cfec..4ac0befb89 100644
--- a/wp-includes/class-wp-customize-control.php
+++ b/wp-includes/class-wp-customize-control.php
@@ -1243,7 +1243,8 @@ class WP_Customize_Theme_Control extends WP_Customize_Control {
 	 */
 	public function content_template() {
 		$current_url = set_url_scheme( 'http://' . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'] );
-		$preview_url = add_query_arg( 'theme', '{{ data.theme.id }}', $current_url );
+		$preview_url = esc_url( add_query_arg( 'theme', '__THEME__', $current_url ) ); // Token because esc_url() strips curly braces.
+		$preview_url = str_replace( '__THEME__', '{{ data.theme.id }}', $preview_url );
 		?>
 		<div class="theme" tabindex="0" data-preview-url="<?php echo esc_attr( $preview_url ); ?>" aria-describedby="{{ data.theme.id }}-action {{ data.theme.id }}-name">
 			<# if ( data.theme.screenshot[0] ) { #>
diff --git a/wp-includes/version.php b/wp-includes/version.php
index d5a1f7fe8b..1cf035bbd4 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.2-beta4-32133';
+$wp_version = '4.2-beta4-32134';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.