diff --git a/src/node/hooks/express/tests.js b/src/node/hooks/express/tests.js
index 7b32a322d..87edc2a09 100644
--- a/src/node/hooks/express/tests.js
+++ b/src/node/hooks/express/tests.js
@@ -17,7 +17,7 @@ exports.expressCreateServer = function (hook_name, args, cb) {
     files = files.filter((f) => f.endsWith('.js'));
 
     console.debug('Sent browser the following test specs:', files);
-    res.setHeader('content-type', 'text/javascript');
+    res.setHeader('content-type', 'application/javascript');
     res.end(`var specs_list = ${JSON.stringify(files)};\n`);
   });
 
@@ -49,6 +49,8 @@ exports.expressCreateServer = function (hook_name, args, cb) {
 
       content = `describe(${JSON.stringify(specFileName)}, function(){   ${content}   });`;
 
+      if(!specFilePath.endsWith('index.html')) res.setHeader('content-type', 'application/javascript');
+
       res.send(content);
     });
   });