Web-exposed Screen Profiler

In the mid-2000s, the Window object's capabilities expanded with the introduction of the screen API. The screen API provides information about the user's display, such as screen resolution, color depth, and available screen space. This API allowed developers to create web applications that could adapt to different screen sizes and resolutions.

The screenLeft and screenTop properties were first introduced in Internet Explorer 4, which was released in 1997. They were later adopted by other major browsers, including Netscape Navigator and Mozilla Firefox. The properties were included in the W3C's CSSOM View Module, which was released as a recommendation in 2008.

In the early days of the web, the screenLeft and screenTop properties were useful for creating pop-up windows that were positioned relative to the screen, rather than the browser window. They were often used for displaying ads, as well as for creating custom login forms and other UI elements that needed to be positioned outside of the browser window.

Additional Credits:
UAParser.js
Accordion CSS.