  The question of a possible redshift-dependence of gamma-ray absorption due to
gamma-gamma pair production of jet photons in the accretion disk and BLR
radiation field in strong-line quasars is investigated. For this relevant
aspects of cosmological black hole and quasar evolution are applied to the
expected pair production opacity of GeV-photons in those sources. I demonstrate
that for positively evolving and non-evolving accretion rates over cosmological
time, detectable gamma-ray optical depths originating within the AGN system
will show a redshift-dependence in the LAT energy range with larger opacity
from sources at higher redshifts. This introduces ambiguities in the
interpretation of spectral absorption features, and complicates approaches for
estimating the evolution of the extragalactic background light by probing the
gamma-ray horizon when using blazars whose external photon fields are involved
in gamma-ray production.
