thankfully it's usually the other way around: the glass is opaque and only transparent with power. So you don't need to worry about an ill-timed power outage.
That's called PDLC film (polymer-dispersed liquid crystal) and it's a thin layer you can apply to anything. It's literally liquid crystal droplets suspended in a plastic sheet layered between transparent ITO conductors (indium-tin-oxide).
A distinctive feature of panels layered with this is that there must be a bezel along at least one edge through which to run the power. I don't see any in the right places on the doors for these, so nope, these are just clear glass without any PDLC film.