AMP tag issue!

You have to share the URL for your AMP page that has the problem.

Also, share the plugins you have active.

@elenmartinez Please try turning off Autoptimize. It may be conflicting. The issue is that the following style element is getting stripped somehow:

<style amp-boilerplate>body{-webkit-animation:-amp-start 8s steps(1,end) 0s 1 normal both;-moz-animation:-amp-start 8s steps(1,end) 0s 1 normal both;-ms-animation:-amp-start 8s steps(1,end) 0s 1 normal both;animation:-amp-start 8s steps(1,end) 0s 1 normal both}@-webkit-keyframes -amp-start{from{visibility:hidden}to{visibility:visible}}@-moz-keyframes -amp-start{from{visibility:hidden}to{visibility:visible}}@-ms-keyframes -amp-start{from{visibility:hidden}to{visibility:visible}}@-o-keyframes -amp-start{from{visibility:hidden}to{visibility:visible}}@keyframes -amp-start{from{visibility:hidden}to{visibility:visible}}</style>

It is required for a page to be valid AMP. I can see that Autoptimize is moving it into a separate external stylesheet, in particular https://miguelrivasespana.es/wp-content/cache/autoptimize/css/autoptimize_5e2b569eacd096b6f7cad0fa561a0128.css

So that needs to be prevented. You may be able to do this yourself via the autoptimize_filter_css_exclude filter. But in reality, Autoptimize CSS handling should be disabled entirely for AMP responses because the AMP plugin will automatically inline, minify, and tree-shake CSS. So it would perhaps be better to disable the Autoptimize plugin’s CSS optimizations entirely. For example, per the plugin docs:

add_filter( 'autoptimize_css_do_minify', function( $minify ) {
    if ( function_exists( 'is_amp_endpoint' ) && is_amp_endpoint() ) {
        $minify = false;
    }
    return $minify;
} );

I’ll open an issue on the plugin so that AMP’s special stylesheets can be exempted handling.

Here’s a pull request you can try: https://github.com/futtta/autoptimize/pull/223

It should fix the issue, but I have not tested it myself.

The pull request for Autoptimize has been merged. So watch for a new version of that plugin and you can try re-activating it, or try applying the patch sooner.

@naveenrocks Please open a new topic.