99% of the time I'm forced to use a site that turns out to be a horribly bloated SPA that I only get to see after enabling JS, and which will do irritating things like what is described in the article, among others, it's to do something that could've easily been done with a simple HTML form and perhaps a bit of JS enhancement.
Single-page app. Basically JS takes over most browser functions and you have your application running in a single "page", so to speak. For example, clicking on a link is a state transition in the app, so instead of telling the browser to go to the new link, the app will push new history to the browser history stack and do the transition itself.
99% of the time I'm forced to use a site that turns out to be a horribly bloated SPA that I only get to see after enabling JS, and which will do irritating things like what is described in the article, among others, it's to do something that could've easily been done with a simple HTML form and perhaps a bit of JS enhancement.