Fluxbox - Fluxbox is a window manager for X that was based on the Blackbox 0.61.1 code.
Witch - Welcome to the world of W. i. t. c. h.
IceWM - icewm home page . Bug Tracking. If you have a patch, a bug report or a feature request to submit, please do so at the icewm project page at SourceForge.
Hyperswitch - HyperSwitch provides a compelling alternative to HyperDock for keyboard junkies. What's New
KWin - KWin is a window manager for the X Window System, and is in the process of becoming a Wayland...
Contexts - Switch between application windows effortlessly — with Fast Search, a better Command-Tab, a Sidebar or even a quick gesture. Free trial available.