  Beaton, Owczarek and Xu (2019) studied generating functions of Kreweras walks
and of reverse Kreweras walks in the quarter plane, with interacting
boundaries. They proved that for the reverse Kreweras step set, the generating
function is always algebraic, and for the Kreweras step set, the generating
function is always D-finite. However, apart from the particular case where the
interactions are symmetric in $x$ and~$y$, they left open the question of
whether the latter one is algebraic. Using computer algebra tools, we confirm
their intuition that the generating function of Kreweras walks is not
algebraic, apart from the particular case already identified.
