The success of the self-consistent DFT approach to mesoscopic systems [18] in general, and specifically to atomic nuclei [19,20,21], has its roots in the SSB mechanism that incorporates essential short-range (pairing) and long-range (spatial) correlations within a single deformed Slater determinant. The deformed states provide a basis for the symmetry-projected DFT approaches, which aim at including beyond-mean-field correlations through the restoration of broken symmetries by means of projection techniques [22].