The best Window Manager alternative to RMUX is GNU Screen, which is both free and Open Source. If that doesn't suit you, our users have ranked more than 10 alternatives to RMUX and three of them are Window Managers so hopefully you can find a suitable replacement. Other interesting Window Manager alternatives to RMUX are byobu and Twin.
Offers full-screen terminal multiplexing with independent windows, VT100 emulation, scrollback, and copy-paste. Supports ANSI standards, detaching, and persistent background process execution for shells or commands across Unix-like systems.
Byobu is a GPLv3 open source text-based window manager and terminal multiplexer. It was originally designed to provide elegant enhancements to the otherwise functional, plain, practical GNU Screen , for the Ubuntu server distribution.
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