Google Speed : Prioritize visible content

Hi there,

I’ve many websites and they all scored 100/100 at the Google PageSpeed Insight. But recently they all get the error “Prioritize visible content” in the “desktop” tab (and I didn’t do anything, I guess the Speed test has recently been updated) :

Prioritize visible content
Your page requires additional network round trips to render the above-the-fold content. For best performance, reduce the amount of HTML needed to render above-the-fold content.
The entire HTML response was not sufficient to render the above-the-fold content. This usually indicates that additional resources, loaded after HTML parsing, were required to render above-the-fold content. Prioritize visible content that is needed for rendering above-the-fold by including it directly in the HTML response.

    Only about 48% of the final above-the-fold content could be rendered with the full HTML response see screenshot show original.

I past some hours on Google but I can’t find a solution.

Here is the speedtest result (don’t forget to look at the “desktop” tab, not at mobile) and here is one of my websites.

As you can see the website is very tiny, you don’t need to scroll down so there is not any “above-the-fold content”.

I tried to generate my critical css with both https://jonassebastianohlsson.com/criticalpathcssgenerator/ and the paid version https://criticalcss.com/generate

Here is a screenshot of my Autoptimize’s Settings

Thank you