Show pixel preview in prototypes

Hi everyone, I’m a teacher using Figma in a design class. We’re currently working on retro-engineering design prompts. For example, “design Spotify on Game Boy Classic”.

The “pixel preview” option is perfect for that while in design mode, however, it doesn’t seem to be available on prototypes. This is 1980, we don’t want super smooth x4 retina anti-aliasing here!

Any idea how to enable “pixel preview” in prototype mode?

Thanks so much in advance!