TAG image vs picture

Hello

On our site we used Imagify plugin and acivated the Webp option with use of <picture> tag option (cause the rewrite with Htaccess don’t work).

But now on Chrome the principal image don’t appear and when I click on pictures in the article instead of open in a popin they open in a new browser.
A JS missing?
For example https://www.virtualmagie.com/articles/autres/trucs-du-metier/tutoriel-fabriquer-un-tapis-de-close-up-multi-fonctions/

Here the answer of a Imagify dev:

Regarding your first question, yes, I think there may be some issue with JS. If I change the following CSS rule:
body .td-backstretch { opacity: 1; }

Then also remove this one:
(applied inline to <picture> element: element.style { translate3d(-50%, -16px, 0px) scale(1.05, 1.05) }

I can see the principal image:

The JS may be looking for elements when instead of <picture> tags?
I would contact the theme or plugin developer to see if they have any solutions to allow use of <picture> elements.