amphtml: Doubleclick served a4a ads do not work when loaded in a PWA with shadowdom

What’s the issue?

When loading an AMP document into a shadowdoc as part of PWA, should the document contain an amp-ad of type “doubleclick” which loads an amp4ads based ad, the ad fails to load due to numerous errors related to No ampdoc found for [object HTMLHtmlElement].

How do we reproduce the issue?

A demo is available here: https://d1kvlucx6m02nr.cloudfront.net/

Upon first ( uncached ) load the ad loads correctly as the document is yet to be loaded within the shell container.

However as soon as navigation occurs & the shell container is used the ad fail to load.

1. Navigate to https://d1kvlucx6m02nr.cloudfront.net/
2. Click on “Article 1”

What browsers are affected?

All browsers

Which AMP version is affected?

HTML shadows – Version 1910071803120

Based on previous issues related to PWA, shadowdoc & Doubleclick it looks like there may have a been a regression.

• https://github.com/ampproject/amphtml/issues/9679
• https://github.com/ampproject/amphtml/pull/9999

Additionally the a4a ad example loaded via projects example of a PWA is also broken. http://localhost:8000/pwa/