With Content-Security-Policies (**CSP**) activated, the below code in line 10 of file https://github.com/captcha-com/reactjs-captcha/blob/master/src/captcha-helper.js ``` var f = new Function(responseText); ``` is **blocked**. Indeed `Function()` method is [blocked by default by CSP](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Security-Policy/script-src). So the captcha does not work. Therefore, to make it work, we have to add the below exception in our content security policies: ``` script-src 'unsafe-eval'. ``` This reduces the protection against certain types of DOM-based XSS bugs... So on one side we increase the security with the captcha but in another side we decrease it by "unsafing" javascript evaluation methods.