  We study dynamic features of a plasma consisting of gluons whose infrared
dynamics is improved by the Gribov-Zwanziger quantization. This approach
embodies essential features of color confinement which set the plasma apart
from conventional quasiparticle systems in several aspects. Our study focusses
on a boost-invariant expansion for in- and out-of-equilibrium settings, which
at late times can be characterized by the sound velocity, $c_s$, and the shear,
$\eta$, and bulk, $\zeta$, viscosities. We obtain explicit expressions for the
transport coefficients $\eta$ and $\zeta$ and check that they are consistent
with the numerical solutions of the kinetic equation. At high temperature,
keeping both the Gribov parameter and the relaxation time constant, we find a
scaling $\zeta/\eta \propto 1/3 - c_s^2$ which manifests strong breaking of
conformal symmetry in contrast to the case of weakly coupled plasmas.
