Specifically, while 3 leptons are topological charges here (for electric charge quantization), there are also fluxons/Abrikosov vortex-like topological structures, which simplest knots resemble baryons - including e.g. explanation why proton is lighter than neutron.
The neutron (as SO(4) physics shows) simply is a proton with a coupled electron + an additional charge generation wave of the proton. A neutron cannot simply be produced outside a nucleus as it is the basic connection between p-p electro-strong (deuterium) or strong bonds as in 4-He.
The standard model math is based of SO(3)xSU(2)xU1 what is garbage as the resulting symmetries do not allow for stable, homogeneous flux on a 4D manifold. Only the double torus cover SU(2)x(SU(2) = SO(4) allows stable, homogenous flux as it (Clifford torus) also is a minimal Lagrangian (= stable).
The problem with mathematicians is that they believe O(4) means 4 common center rotations what is OK for a fully connected body but is neither stable nor homogeneous. SO(4) also owns the double torus cover with 4 connected rotations that is stable and homogeneous. So this is a 4D 4 rotation Möbius surface.
Standard model topological charge has once been defined as winding number, hence it is just a mathematical fantasy. Charge of any kind can only be produced by following the Maxwell laws, what means toplogically fully enclosed (in one plane) EM flux produces a "boarder charge". This is why I urge people (mathematicians) doing theoretical physics to go in a beginners lab and do some basic experiments like Faraday's induction before they repeat SM mantras that have no use at all.