Microsoft's open-source editor (the OSS core, not the proprietary build). Surpassed all competitors; the foundation Cursor, Windsurf, and Codium build on.
From Wikipedia
Visual Studio Code is an integrated development environment developed by Microsoft for Windows, Linux, macOS and web browsers. Features include support for debugging, syntax highlighting, intelligent code completion, snippets, code refactoring, and embedded version control with Git. Users can change the theme, keyboard shortcuts and preferences, as well as install extensions that add functionality, including to extend its capabilities to function as an IDE for other languages.