> As a datapoint I work in 3.8. I will try to move to 3.9 when it seems
> fruititious - but I probably will not work in it until Seaside, Magma
> and a few other important pieces are stabilized in it.

As a datapoint Magma will be ported to 3.9, but I have not had time to
even look at that yet.

 - Chris