  We consider massive scalar field perturbations in the background of black
holes immersed in Chaplygin-like dark fluid (CDF), and we analyze the photon
sphere modes, the de Sitter modes as well as the near extremal modes and
discuss their dominance, by using the pseudospectral Chebyshev method and the
third order Wentzel-Kramers-Brillouin approximation. We also discuss the impact
of the parameter representing the intensity of the CDF on the families of
quasinormal modes. Mainly, we find that the propagation of a massive scalar
field is stable in this background, and it is characterized by quasinormal
frequencies with a smaller oscillation frequency and a longer decay time
compared to the propagation of the same massive scalar field within the
Schwarzschild-de Sitter background.
