AMP in Static HTML export

When using next export to do Static HTML export statically prerender pages, Next.js will detect if the page supports AMP and change the exporting behavior based on that.

For example, the hybrid AMP page pages/about.js would output:

• out/about.html - HTML page with client-side React runtime
• out/about.amp.html - AMP page

And if pages/about.js is an AMP-only page, then it would output:

• out/about.html - Optimized AMP page

Next.js will automatically insert a link to the AMP version of your page in the HTML version, so you don't have to, like so:

<link rel="amphtml" href="/about.amp.html" />

And the AMP version of your page will include a link to the HTML page:

<link rel="canonical" href="/about" />

When exportTrailingSlash is enabled the exported pages for pages/about.js would be:

• out/about/index.html - HTML page
• out/about.amp/index.html - AMP page