There is previous similar question but solution there didn't work for me in Ubuntu 16.04. I mean:
gkbd-keyboard-display -l us,intl
The commands below work but I want to be able to specify which layout variant not just basic layout or current one.
gkbd-keyboard-display -l us
gkbd-keyboard-display -g 1
Well, found the trick after trying the GUI then watch which command it is launching.
So, here is the command that works, which uses tab
\t
as separator: