Lighthouse fails to dismiss page dialogs

[pmeenan]

Lighthouse is having issues with pages that have dialogs (at least some types of dialogs) and times out when loading the page.

FWIW, WebPageTest had similar issues and now tries first to "accept": false the dialog and if that fails tries "accept": true. Similar logic in Lighthouse should make it more robust for pages with dialogs.

Test page: http://www.dlsite.com/

Log:

  status Loading page & waiting for onload +7ms URL, Viewport, ViewportDimensions, ThemeColor, Manifest, ChromeConsoleMessages, ImageUsage, Accessibility, EventListeners, AnchorsWithNoRelNoopener, AppCacheManifest, DOMStats, OptimizedImages, ResponseCompression, TagsBlockingFirstPaint, WebSQL
  Driver:warn confirm dialog opened by the page automatically suppressed. +4s
  method <= browser ERR:error Page.handleJavaScriptDialog +1ms 

[pmeenan]

It looks like Lighthouse only tries "accept":true and tries that first and it intentional.

[pmeenan]

At a minimum, the test should fast-fail when the dialog dismissal fails (whether or not it falls back to false).

[patrickhulce]

Ah thanks for the tip @pmeenan we've been struggling with this in CI too!