Modals can be done with CSS pretty easily (with either :checked and a label to activate the modal or :target and a link to activate it or with details/summary e

Modals can be done with CSS pretty easily (with either :checked and a label to activate the modal or :target and a link to activate it or with details/summary etc.), so can form validation (the required and pattern attributes), and lazy loading (add the loading="lazy" attribute for images and iframes). Infinite scroll can't really be implemented easily but in theory it's possible with server support (I'll make a demo and get back to you).