Hey romagromov,

I am really sorry for the delay of this reply as it is a weekend for us here.

Unfortunately those attributes can't remove is because it will messed up with the child comment.

By the way, I will consult with our developer regarding this when week start tomorrow,

Hey romagromov,

Those attributes not allowed on elements <li>

I already consult with our developer regarding this, unfortunately that was not possible to remove those attributes is because the system is depend on this attribute to arrange the child comment. And these errors you show to us is actually not causing any error in your site, just that some validators don’t accept this attribute assign in <li> tag.

Regarding your second error, it seems like different validators have their own datetime format. By the way, you can disable "Enable Schema" from your backend > Komento > configuration > Schema and see how it goes?