Recently, one of our users reported getting this message when running in Chrome:
It’s not one you need to worry about. It only happens when you are running with the Chrome Debugger open. It’s complaining that it does not have the extra files it needs to display the jQuery source code properly. Since it is very unlikely that you will have any need to look at that code, it doesn’t matter.
If it really bugs you, you can go into the Debugger Preferences and turn off the warning. The setting to turn off is “Enable Source Maps”.
There is more info here.