bmux bmux is a free, open-source browser built as a multiplexer for the agentic era. It offers split panes with independent address bars, named sessions, and multiple profiles inside a single window. Users browse with keyboard shortcuts while AI agents work in background sessions through a CLI; they can attach to an agent session whenever they want to inspect the work. Layouts can be saved, windows detached while pages keep running, and floating reference panes sit beside the main view.