Sorry, i missed this statement

downloadLink.dispatchEvent(event_1);

which causes ChromeHeadless to crash in Karma

I'm experiencing what I think is a related issue. I'm using chromeless (via the aws lambda proxy) and started having weird timeouts recently. When I initiate a click event on a download link, the chromeless lambda proxy stops communicating with the headless chrome instance. Perhaps unrelated here, but chromeless stops responding for roughly 30 minutes then appears to "reset" and works normally again until a download is started.

The chromium binary is running in a Linux like environment inside an aws lambda instance. From what I can tell the chromium binary is the latest stable release. I ran a headless chrome session on my local machine (Ubuntu 17.10, Chrome 64.0.3282.140 (Official Build)) and got a segfault when the download link is clicked.

tldr; looks like this happens on linux too.

It's not clear what the specific error here is. Can you post some logs and perhaps a more reduced test case?

Sample Test script:

var buffer = new Blob(['hello world']);
var downloadLink = document.createElementNS('http://www.w3.org/1999/xhtml', 'a');
downloadLink.download = 'sample.txt';
var dataUrl = window.URL.createObjectURL(buffer);
downloadLink.href = dataUrl;
var clickEvent = document.createEvent('MouseEvent');
clickEvent.initEvent('click', true, true);
downloadLink.dispatchEvent(clickEvent);
setTimeout(function () {
    window.URL.revokeObjectURL(dataUrl);
    dataUrl = undefined;
});

When running this test script using karma, below error thrown in ChromeHeadless v64

Failed to create a temp dir at C:\Users\ARUMUG~1\AppData\Local\Temp\karma-87812328

Whereas there was no issues in v63

That error message seems to be coming from Karma. Maybe a problem similar to this? https://github.com/karma-runner/karma-opera-launcher/issues/10

With all configurations intact, the issue reproduces in chrome v64 but not in v63 (downgraded the chrome version in same machine to get this worked). I am not sure how this problem is related to Karma. Anyways thank you for the help.

Thank you for providing more feedback. Adding the requester to the cc list.

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