Poster of gutenberg video block to cover all video area

Try this jQuery

jQuery("#myvideo").hover(function(event) {
    if(event.type === "mouseenter") {
        jQuery(this).attr("controls", "");
    } else if(event.type === "mouseleave") {
        jQuery(this).removeAttr("controls");
    }
});

Thanks man,

You're great!

I'm recommending this theme to everyone.

Awesome - glad to be of help