🚨 Error: Cannot destructure property `ampdoc` of 'undefined' or 'null'.

Details
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**Error report:** [link](http://go/ampe/CLKV-_Th15OhGw)
**First seen:** Oct 14, 2021
**Frequency:** ~ 1,874/day

Stacktrace
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Error: Cannot destructure property `ampdoc` of 'undefined' or 'null'.

    at amp (multidoc-manager.js:491:21)

    at closeShadowRoot_AMP_PRIVATE_ (multidoc-manager.js:149:13)

    at close (amp-next-page/1.0/page.js:181:27)

    at pause (amp-next-page/1.0/service.js:415:24)

    at map (amp-next-page/1.0/service.js:408:9)

    at hidePreviousPages_AMP_PRIVATE_ (amp-next-page/1.0/service.js:341:8)

    at forEach (amp-next-page/1.0/service.js:332:16)

    at updateVisibility (amp-next-page/1.0/service.js:532:13)

/cc @ampproject/release-on-duty

Start by tracing the stack from extensions/amp-next-page/1.0/service.js and page.js into src/multidoc-manager.js, especially the referenced lines. Determine why the ampdoc value is missing during close and document a reproducible case or regression test; done means the production error no longer occurs.

Written by the indexing model from the issue text.