Bug#265595: xmodmap.1x.gz: how to make the Windows key into the Control key
Our control keys have died and there is no keyboard store on the island.
Our eyes spot a key with the Windows(TM) logo on it that we never use.
We wish to make this Windows key into a spare control key.
$ man xmodmap et. al. don't even say what the name of this key is.
xev shows that it is called Super_L.
Our wild guess modeled on xmodmap's "Swap Caps_Lock and Control_L"
example fail. Also we don't need to do a full swap. The solution to
the above sounds like a good example for the xmodmap man page.