Actually, I haven't got the chance to try as when I now turn my Macbook on
and off again, I only get the Grub menu in very low resolution screen and
have no other choice but to choose the Trisquel line.
When the graphical interface shows up, resolution is still low and I have no
control whatsover on th keyboard ! Doesn't sound good to me.
I wish I could at least install Trisquel again (in case that would solve the
problem), but holding the C key at startup has no effect, so I can't boot on
the Trisquel DVD...
Any help will be very precious !