Invalid CDATA attribute "noscript > style : boilerplate – old variant"

Hi,

Google Search Console reports for every page this error (in French in my case, sorry)

Attributs CDATA de la feuille de style manquants ou incorrects : noscript > style : boilerplate – old variant

I suppose this refers to this snippet (the only place where “boilerplate” us used) that is on every amp page on my site:

<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>
<noscript><style amp-boilerplate>body{-webkit-animation:none;-moz-animation:none;-ms-animation:none;animation:none}</style></noscript>

No idea why amp-boilerplate attribute is allowed in the ‘normal’ <style> tag while it is not allowed in the <noscript><style> tag… but there it is. Or is that “old variant” the key here?

Anybody an idea how to solve this? Should it be amp-custom instead?

https://ww.wp.xz.cn/plugins/amp/