New CSS Viewport Units Do Not Solve The Classic Scrollbar Problem

Browsers shipped a new set of CSS viewport units in 2022. These units make it easier to size elements in mobile browsers, where the browser’s retractable UI affects the height of the viewport as the user scrolls the page. Unfortunately, the new units do not make it easier to size elements in desktop browsers, where classic scrollbars affect the width and height of the viewport.
The following video shows a desktop browser with classic scrollbars. As we resize the viewport (dashed line) in d