My higher-level goal is to use video in Figjam, and I got close to this by embedding links to Figma prototypes that use video, configured to hide the Figma UI. Yet, the preview size in Figma leaves a lot to be desired about how this presents.
Ideally, interactive previews should be as adjustable as their static counterparts. But a stop-gap idea might be to rely on the prototype configuration and borrow the device frame.