Hi,
I don't know whether this belonged in -bugs or -translators, so I just picked one.
This seems to affect versions 9.4 onward.
When changing tuples_only to on, the Spanish translation incorrectly shows:
"Mostrar sólo filas está desactivado."
# \pset tuples_only off
Mostrar sólo filas está desactivado.
# \pset tuples_only on
Mostrar sólo filas está desactivado.
It should read:
"Mostrar sólo filas está activado."
I've attached a patch to fix this.