  Neutrinos in a core-collapse supernova can undergo fast flavor conversions
with a possible impact on the explosion mechanism and nucleosynthesis. We
perform the first non-linear simulations of fast conversions in the presence of
three neutrino flavors. The recent supernova simulations with muon production
call for such an analysis, as they relax the standard
$\nu_{\mu,\tau}=\bar{\nu}_{\mu,\tau}$ (two-flavor) assumption. Our results show
the significance of muon and tau lepton number angular distributions, together
with the traditional electron lepton number ones. Indeed, our three-flavor
results are potentially very different from two-flavor ones. These results
strengthen the need to further investigate the occurrence of fast conversions
in supernova simulation data, including the degeneracy breaking of mu and tau
neutrinos.
