Download Largest Contentful Paint in advance in Slideshow CK

To improve site render times, PageSpeed Insights offers to download Largest Contentful Paint in advance, for which it suggests adding class="imgLoaded" to the description of the first slideshow image. Is it possible?
Thanks

Hi
The problem is that the images in the slideshow are loaded by Javascript, this means that they are not loaded when the robot scrolls the page.
Do you have a reference documentation for that ?
CEd

ced1870 wrote: Hi
The problem is that the images in the slideshow are loaded by Javascript, this means that they are not loaded when the robot scrolls the page.
Do you have a reference documentation for that ?
CEd

Excuse me, I haven't understood your question.
What a documentation, please?
I can add screens from  GTmetrix for example.

Thanks

I mean an official text from Google or the W3C about this feature
Ok for the screenshot from GTmetrix, even if I never base any feature from their analysys

Sorry for the delay in responding.

Here is a screenshot from Gtmetrix.


And this is a screen from PageSpeed Insights.



Thanks for the support.

Sorry for the delay in responding.

Here is a screenshot from Gtmetrix.



And this is a screen from PageSpeed Insights.



Thanks for the support.