I ran into the same problem, and I'm not sure why, but it turned out to be that the script link generated by Scripts.Render did not have a .js extension. Because it also does not have a Type attribute the browser was just unable to use it (chrome and firefox).
To resolve this, I changed my bundle configuration to generate compiled files with a js extension, e.g.
var coreScripts = new ScriptBundle("~/bundles/coreAssets.js")
.Include("~/scripts/jquery.js");
var coreStyles = new StyleBundle("~/bundles/coreStyles.css")
.Include("~/css/bootstrap.css");
Notice in new StyleBundle(...
instead of saying ~/bundles/someBundle
, I am saying ~/bundlers/someBundle.js
or ~/bundles/someStyles.css
..
This causes the link generated in the src attribute to have .js or .css on it when optimizations are enabled, as such the browsers know based on the file extension what mime/type to use on the get request and everything works.
If I take off the extension, everything breaks. That's because @Scripts and @Styles doesn't render all the necessary attributes to understand a src to a file with no extension.