Network error on generated download in Chrome

Question

in my web app, I want to provide a download for a message log. This is done by the following javascript function:

let download = (content, filename) => {
    let uriContent = "data:application/octet-stream;charset=utf-8;base64," + btoa(content);
    let link = document.createElement('a');
    link.setAttribute('href', uriContent);
    link.setAttribute('download', filename);
    let event = new MouseEvent('click');
    link.dispatchEvent(event);
};

The function is executed by a mouse click and works fine in most cases.

However, when the file becomes a little bigger ( > ~3MB), the download fails in Chrome with a network error.

The same download works fine in other browsers like Firefox. Incognito mode did not solve the issue.

Can I change something in my code to make the download work? Or is this some bug (or feature) of Chrome that prevents the download?

Answer 1

There is a limit of (slightly less than) 2MB. See https://bugs.chromium.org/p/chromium/issues/detail?id=69227

You can workaround it using blob urls. https://developer.mozilla.org/en-US/docs/Web/API/URL/createObjectURL

let download = (content, filename) => {
    let uriContent = URL.createObjectURL(new Blob([content], {type : 'text/plain'}));
    let link = document.createElement('a');
    link.setAttribute('href', uriContent);
    link.setAttribute('download', filename);
    let event = new MouseEvent('click');
    link.dispatchEvent(event);
};