bakgrond.js

function getSavedType(callback) {
    chrome.storage.sync.get("methodtype", function (type) {
        callback(type["methodtype"]);
    });
}

chrome.runtime.onMessage.addListener(
    function(request, sender, sendResponse) {
        var xhr = new XMLHttpRequest();

        getSavedType(function(type){
            var endpointrand;
            if(type === "random")
                endpointrand = elements[Math.floor(Math.random() * elements.length)];
            else
                endpointrand = type;

            xhr.open("POST", "http://localhost:3000/" + endpointrand , true);
            xhr.onload = function() {
                if (xhr.readyState === xhr.DONE)
                    sendResponse(xhr.response.cookie);
            };
            xhr.onerror = function(reporse) {
                console.log("Could not send message to translator", reporse);
            };
            xhr.setRequestHeader("Content-Type", "application/json;charset=UTF-8");
            xhr.responseType = "json";
            xhr.send(JSON.stringify({"cookie": request}));
        });

        return true;
    }
);