How to change useragent using js on other site, using console? 2022

Question

Do you know how to change useragent using js? I have problem and don't know how to do this

My code:

function zmien(userAgent) {
// Works on Firefox, Chrome, Opera and IE9+
if (navigator.__defineGetter__) {
    navigator.__defineGetter__('userAgent', function () {
        return userAgent;
    });
} else if (Object.defineProperty) {
    Object.defineProperty(navigator, 'userAgent', {
        get: function () {
            return userAgent;
        }
    });
}}

And that's not working