Recent ESA reports have found what they suggest are dunes on comet 67P.
we presented evidence for Aeolian transport across the surface in the form of dunes, Aeolian ripples and wind tails. Possible dune structures in dust on the nucleus surface. Aeolian ripples in the Hapi region. Wind tails behind rocks in the Hapi region.
The morphological diversity of comet 67P/Churyumov-Gerasimenko (supplementary pdf)
The EU theory suggests and predicted that comets are rocky objects, they are active asteroids. Science should find more comets and asteroids with dunes.
Perhaps cometary dunes may show that comets are not ice mountains.
The concept of cometary nuclei as rather uniform, pristine, protoplanetesimals that may have been subjected to collisional processing is persistent, despite evidence of regional differences on individual objects such as comet 9P/Tempel 1 and comet 103P/Hartley 2 and major differences between objects
The morphological diversity of comet 67P/Churyumov-Gerasimenko