Breakup of the current-vortex sheet and associated reconnection at t = 10. Panel a: current and vorticity density at z = 0. Panel b: spatial distribution of reconnection rate measured as the parallel electric field integrated along field lines traced from locations in the plane z = 0.23. Both panels show both viscosity models with isotropic shown on the left half of each figure and switching on the right. The current-vortex sheet remains stable in the isotropic case while that in the switching case has been fragmented by the KHI. The resultant small-scale reconnection in the rolls produces localised pockets of strong vorticity and current density.