  Transformation properties of a class of generalized Kawahara equations with
time-dependent coefficients are studied. We construct the equivalence groupoid
of the class and prove that this class is not normalized but can be presented
as a union of two disjoint normalized subclasses. Using the obtained results
and properly gauging the arbitrary elements of the class, we carry out its
complete group classification, which covers gaps in the previous works on the
subject.
