Anthony Ricaud, writing for the Web Performance Calendar, on the extra load that JavaScript can put on your site, and how you can replace some things with basic HTML and CSS:
Relying on solutions provided natively by browsers enables you to benefit at low cost from the expertise of the community creating web standards. These solutions generally have the advantage of using less code, thus reducing maintenance efforts for a development team (for example, no need to update the libraries used).
In this article, we will explore some of these native solutions that are available to the majority of your users.
It’s things like smooth scrolling, sticky items, carousels, etc. — those all can be implemented using pure CSS nowadays.