  Conditions for strong first-order phase transition and generation of
observable gravitational wave (GW) signals are very restrictive to the profile
of the Higgs potential. Working in the minimal extension of the SM with a new
gauge singlet real scalar, we show that the production of signals relevant for
future GW experiments, such as LISA, can favor depleted resonant and
non-resonant di-Higgs rates at colliders for phenomenologically relevant
regimes of scalar mixing angles and masses for the heavy scalar. We perform a
comprehensive study on the emergence of these di-Higgs blind spot
configurations in GWs and also show that di-boson channels, $ZZ$ and $WW$, can
restore the phenomenological complementarities between GW and collider
experiments in these parameter space regimes.
