Power-of-two dimension conjecture for finite-dimensional comodules of the FRT algebra

Let $\mathcal{A}_{ff}$ be the FRT algebra considered in the paper, and let a finite-dimensional comodule mean a finite-dimensional comodule over $\mathcal{A}_{ff}$. Power-of-two dimension conjecture. Every finite-dimensional comodule of $\mathcal{A}_{ff}$ has dimension equal to a power of two; equivalently, its dimension is $2^n$ for some nonnegative integer $n$. This is motivated in the supplied text by computations for tensor products of two and three fundamental comodules and by representation theory of related quantum groups, but no resolution is given.