Ok, its not the worse thing in the world, but the autoComplete in the whisper box has stopped working You know where you start to type in a members name and it gives you all the choices
Stopped working? or never did? After re-uploading the file, check that the permissions are correct on the file you just uploaded. The easiest way to do this if you don't know how is to point your web browser to your "vanilla/js/ac.js" file (wherever it is located on your server).
Correct permissions being that the webserver is able to access the file and serve it out. If you point your browser to the file and see something besides a 403 Forbidden error we know it's not permissions and something else is afoot.