Have you ever wondered what version of PHP your website is running? Or had some really specific question about how PHP is configured and what is enabled/disabled on your site?
When a web page scrolls, that’s a DOM event. I can find out how far a window has scrolled at any time with window.scrollY.
One of the unique job responsibilities of a front-end developer is to make the sites we build work “acceptably” across the browsers the project has decided to support.