I am interested in classifying Hopf or bialgebras up to cocycle deformation
rather than up to isomorphism. For this, it seems natural to extend the framework
to coquasi-bialgebras, the dual notion of quasi bialgebras due to Drinfeld.
In terms of extensions, I will give some method of constructing coquasi-bialgebras
and classifying them up to coquasi-isomorphism.