@Soy_Magnus @anonymous @Zergling_man >https://github.com/ruffle-rs/ruffle
It's a project that's more or less dead and never really worked in the first place. I have a linux binary I'd be willing to share with you but it's also very old and I can't remember how I obtained it so results may vary.
Since it's just a video and no interaction is required you'd be better off trying out some of the free (as in freedom) flash players out there until you get something that works for your device.
You can, of course, always use windows with it's time turned back before they forcibly disabled flash and then just install any of the plethora of flash executables out there.