Yes, i've seen them multiple times too. It looks like it's burned in the ground 'though. And always only one, two, three prints, never a whole trail.
I think it is a stock ground texture/mesh that has these footprints. I have seen it in other places where no dragon was to be found. I guess it is one of those things that makes you pause before you unleash the dragon menace seeing foot prints that are bigger than you.
A few days ago I noticed them for the first time too. Mine where in the snow, looks even cooler then. The ones I saw appeared where a dragon was landing if I'm not mistaken.