  The nonrelativistic energy together with relativistic and quantum
electrodynamic corrections for all the molecular hydrogen isotopologues (D$_2$,
T$_2$, HD, HT, DT) were evaluated without expansion in the electron-nucleus
mass ratio.
  The obtained results significantly improve the uncertainty of theoretical
predictions, reaching a value below 1 MHz for the total dissociation energy. We
observe good agreement with the experimental value for D$_2$ and $3\,\sigma$
discrepancy for the HD molecule, while no experimental values for the
dissociation energy of molecules involving tritium have yet been obtained.
