diff --git a/packages/node_modules/node-red/red.js b/packages/node_modules/node-red/red.js
index cb247ee48..d602cfe4a 100755
--- a/packages/node_modules/node-red/red.js
+++ b/packages/node_modules/node-red/red.js
@@ -424,7 +424,7 @@ httpsPromise.then(function(startupHttps) {
     if (settings.httpStatic) {
         let appUseMem = {};
         let httpStaticMiddleware = (req, res, next) => next()
-        if (typeof settings.httpStaticMiddleware === 'function' || isArray(settings.httpStaticMiddleware)) {
+        if (typeof settings.httpStaticMiddleware === 'function' || Array.isArray(settings.httpStaticMiddleware)) {
           httpStaticMiddleware = settings.httpStaticMiddleware
         }