Set up web worker on shopify store

I have created a shopify app that uses the graphql api and gets data.

I want to set up the fetch on another thread and want to use a web worker I have created the worker.js in the assets folder but the domain of this file is on the https://cdn.shopify.com and not https://mystore.myshopify.com/ domain and the worker wont work as I get the error "cannot be accessed from origin"

Here is the worker I am using to test getting data

var worker;
testWorker();
function testWorker() 
{
    if (typeof(Worker) !== "undefined") 
    {
        if (typeof(worker) == "undefined") 
        {
            worker = new Worker("{{ 'webworkertest.js'| asset_url }}");
        }
        worker.onmessage = function(event) 
        {
            document.getElementById("loopcount").innerHTML = event.data;
        }
    }
    else 
    {
        document.getElementById("loopcount").innerHTML = "Web Worker not supported";
    }
}


function terminateWorker() 
{ 
    worker.terminate();
    worker = undefined;
}

testMainThread();
function testMainThread() 
{
    for (var i = 0; i < 200000; i++) 
    { 
        document.getElementById("loopcount").innerHTML = "Main Thread Counter: " + i;
    }
}

And here is the worker.js file

i = 0;
while (i < 200000) {
    postMessage("Web Worker Counter: " + i);
    i++;
}