diff --git a/application/themehandler.class.inc.php b/application/themehandler.class.inc.php
index 6aaf30592..43c5053ce 100644
--- a/application/themehandler.class.inc.php
+++ b/application/themehandler.class.inc.php
@@ -244,7 +244,7 @@ CSS;
 	 * @return string
 	 * @throws \Exception
 	 */
-	private static function ComputeSignature($aThemeParameters, $aImportsPaths)
+	public static function ComputeSignature($aThemeParameters, $aImportsPaths)
 	{
 		$aSignature = array(
 			'variables' => md5(json_encode($aThemeParameters['variables'])),