Undefined handlers (OnBegin, OnSuccess, etc.) cause a browser evaluation error when unsafe-eval is restricted by the CSP header.

If you modify all of the text in the handlers to functions instead of JavaScript code then those handlers that contain functions will no longer be blocked by the browser (window.stop [function] vs window.stop() [code needing evaluation]). However, the issue is that the handlers that are left blank will be blocked by the browser and cause an error.

Uncaught EvalError: Refused to evaluate a string as JavaScript because 'unsafe-eval' is not an allowed source of script in the following Content Security Policy directive:

Related to Issue #23.