Performance issue with serving files in Karma 1.4

Expected behaviour

I have an Ext JS project with over 500 files. With karma 1.3, it was serving all these files in around 3-5s.

Actual behaviour

With Karma 1.4 and the exact same files, it was taking over 80 seconds to serve these files, which results in a timeout before the tests can even run.

Environment Details

• Karma version (output of karma --version): 1.4

Steps to reproduce the behaviour

1. Simply run npm test with Karma 1.3 and 1.4