Feature description

As discussed in #4074 and reported in the support forum, recent versions of Gutenberg break the AMP Stories editor.

We need to disable the AMP Stories experience if either the user is on WordPress version under 5.3 and/or they have a Gutenberg version that is too new.

Note that if the user does not have any stories created, then the experience would be hidden entirely. See #4201. So this only is needed for users who have existing amp_story posts.

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Acceptance criteria

Implementation brief

QA testing instructions

Demo

Changelog entry