Syntax-highlighted source with copy-to-clipboard. Same WC powers the snippets across all three framework demos.
The block follows the page's data-bs-theme with no wiring. Pass theme to pin it instead.
Tab reaches the active line, then the arrow keys move between line links and Home / End jump to the ends. Each line number is a real link, so middle-click still opens it.
Give the component a height or max-height and the listing scrolls vertically inside it; constrain the width and long lines scroll horizontally.