I have a one problem, my code is working because I'm getting a mistake about: "Refused to execute inline script because it violates the following Content Security Policy directive: "script-src 'self'"."

My code:

function something(){
var script = document.createElement('script');
script.innerHTML =`
Object.defineProperty(navigator, 'userAgent', {
    get: function () { return 'Mozilla/5.0 (Windows NT 6.2; WOW64; rv:28.0) Gecko/20100101 Firefox/28.0)'; }
});`;
document.head.appendChild(script);}

I wanna inject userAgent but I'm blocked. Is there any way to bypass this error?