GLP1R and diabetes mellitus: Glucagon receptor agonism, as a key component of unimolecular incretin poly‐agonists such as glucagon‐like peptide 1 (GLP‐1)/glucagon “dual” or GLP‐1/glucose‐dependent insulinotropic polypeptide (GIP)/glucagon “triple” receptor agonists, is now being investigated in the treatment of type 2 diabetes mellitus, obesity, diabetic kidney disease, and nonalcoholic steatohepatitis (Ambery et al., 2018; Bossart et al., 2022; Jia et al., 2021; Parker et al., 2020, 2022).