Movie S1.

The last snapshot with the instantaneous (not time-averaged) profiles of density and temperatures across the cold surface of the film at Th|Tc=80.4|72.4K. The video illustrates the steady regime of condensation, at which the density profile is almost static, and only the longitudinal Tx (red dots) and transverse Ty (green dots) temperatures in the low-dense vapor experience the natural fluctuations. Profiles in Fig. 9 were obtained by time averaging of these snapshots.