  We investigate the role of higher-form symmetries in non-equilibrium systems
from the perspective of effective actions defined on the Schwinger-Keldysh
contour. To aid our investigation, we extend the coset construction to account
for $p$-form symmetries at zero and finite temperature. Additionally we
investigate how, out of equilibrium, symmetries of the action need not lead to
meaningful conserved currents at the level of the equations of motion. For
reasons that will become apparent, we term symmetries with conserved currents
St\"uckelberg symmetries and those without meaningful conserved currents
non-St\"uckelberg symmetries (NSS). Ordinarily any action constructed
exclusively from building-blocks furnished by the coset construction will have
St\"uckelberg symmetries associated with each symmetry generator. To expand the
set of systems describable by the coset construction, we devise a method by
which NSS generators can be included as well. While 0-form NSS are quite common
in non-equilibrium effective actions, the introduction of $p$-form NSS is
novel. We use these $p$-form NSS to investigate spontaneous symmetry breaking
of $p$-form symmetries. We find that in non-equilibrium systems, whether or not
a symmetry appears spontaneously broken can depend on the time-scale over which
the system is observed. Finally, using our new coset construction, we formulate
actions for a number of systems including chemically reacting fluids,
Yang-Mills theory, Chern-Simons theory, magnetohydrodynamic systems, and dual
superfluid and solid theories.
