The following alerts with jQuery vanilla, and errors out when jQuery gets wrapped by Raven with a Uncaught TypeError: (intermediate value).foo is not a function(…).

var x = function() {}; x.prototype.foo = function() { alert("hi"); }; var d = $.Deferred(); d.then(function(z) { (new z).foo(); }); d.resolve(x); 

This bit us in production, and we've had to disable Raven until this is fixed.

We use the jQuery wrappers for Raven too.