That's from within the propellants tanks of the upper stage after Dragon separation and the microgravity environment saying hello. Lack of acceleration (stage engine is shut off during separation) acting on propellants when looking at them from inertial frame of reference (the tank itself) means they're essentially in free-fall together with the stage propellant tank they're in.
With a slight kick of the Dragon separation, propellants have sloshed and that produced droplets of the liquid fuel and oxidizer (the first image shows the RP-1 fuel tank, the other two the liquid cryogenic oxygen, or LOX tank, while the embedded video interchangeably shows both) within the tanks, interacting with each other while no other external force acts on them any different than the stage itself. Once the stage engine is reignited, some acceleration is introduced back to the tank and it essentially catches up with the propellants, forcing them towards the aft of tanks in the opposite direction to the stage's acceleration vector.
As a corollary, this is the reason why some upper stages require separate ullage motors to push propellants back towards the aft of the tank, while others might use different systems to achieve that, like with attitude control system's vernier thrusters for a slight stage kick, a wick within the tank that supplies fuel through their surface tension, or pressurant ullage gas and a membrane (aka a bladder) to provide propellants pressure in the feed line.
For additional explanation on how liquids slosh in microgravity, see this NASA's ScienceCasts: The Strange Way Fluids Slosh on the International Space Station video presentation of the SPHERES-Slosh experiment: