VULNERABILITY DETAILS
When using a JavaScript to periodically send requests to a webserver, when the webserver responds with an unauthorized header a denial of service is possible as chrome will open one popup for each request asking for credentials which have to be dismissed by the user individually. This also builds up popups in the background, when the tab is no longer in foreground. After returning to it all popups have to be dismissed in order to use chrome again.

VERSION
Chrome 64.0.3282.137 on Android 8.0

This is my first bug report, please tell me how I can improve in the future.