fvwm-window-search (rubygems): A window switcher: search for windows interactively using a patched dmenu utility (the gem fetches & patches it during its installation). This was originally made for Fvwm, but it's been rewritten to work with any EWMH-compliant stacking window manager.  Requires a preinstalled jansson-devel C library.  It differs from rofi & co in that it activates (brings up) windows _during_ the search. 
Keywords: dmenu|fvwm|window-switcher