Comment 5 for bug 1633284

org.onboard.window.landscape width -40
org.onboard.window.landscape height -20

Yeah, not good.

org.onboard.window.landscape y -3
org.onboard.window.landscape x 1278
Depending on your screen size this could mean the keyboard is outside of the screen. Perhaps there's a problem with the code that limits the keyboard's dimensions. What's your screen resolution? One or multiple monitors?

Could you try
gsettings reset org.onboard.window.landscape x
gsettings reset org.onboard.window.landscape y
gsettings reset org.onboard.window.landscape width
gsettings reset org.onboard.window.landscape height
?