Goldstonic pseudoscalar mesons in Bethe-Salpeter-inspired setting

For a two-particle bound-state equation closer to its Bethe-Salpeter origins than Salpeter's equation, with effective-interaction kernel deliberately forged such as to ensure, in the limit of zero mass of the bound-state constituents, the vanishing of the arising bound-state mass, we scrutinize the emerging features of the lightest pseudoscalar mesons for their agreement with the behaviour predicted by a generalization of the Gell-Mann-Oakes-Renner relation.