[F20, KDE] color profile applied 1 s and then disappears

[Frédéric Bron]

> Make sure there's no non-free process clearing the gamma ramps. The
> non-free driver just isn't very XRANDR 1.3 compliant, and I only test
> with the nouveau driver.

Yes, this is the issue. With nouveau, it works and with the nvidia
proprietary driver, it does not. However, the nouveau driver is not
suitable for my children who play minecraft. I posted a bug report on
nvidia but I never see any answer there.
Thanks,
Frédéric