Skewer
Live web development in Emacs
Skewer Mode is an Emacs package for interacting with live JavaScript, CSS, and HTML running inside a web browser. Developers can send expressions or complete buffers from Emacs and evaluate them immediately on an attached page. JavaScript results appear in the minibuffer or a dedicated REPL, while CSS rules and HTML elements can be updated without reloading the document. Multiple browser windows or tabs may connect simultaneously and receive the same submitted code.