I keep accidentally typing Shift-Space which inserts a non-breaking space instead of a regular space. That's why I wanted to edit my keyboard layout. The following example shows how to change Shift-Space to insert a regular space.

Edit layout

On my machine (Fedora) the file is located here:

/usr/share/X11/xkb/symbols/ch

Search for the correct line and change it like this:

- key <SPCE> { [	space, 	nobreakspace,	nobreakspace		]	};
+ key <SPCE> { [	space, 	space,	      nobreakspace		]	};

Apply changes

In order to apply the changes the layout needs to be set again. In my case:

setxkbmap ch de_mac