Unexplained shape shifting ufo recorded airline passenger

Unexplained shapeshifting UFO/Phenomena recorded by an airline passenger.

I have recently come across this video of a shapeshifting object recorded by German tourist on board a plane. The video was shot when the plane was flying at an altitude between 10,000 and 30,000 feet. The object is filmed for over seven minutes above the altitude of the plane and it appears to be moving alongside with the plane. Does anyone have any ideas what it could be? Jelly fish UFO? Ghost? Something from a higher dimension? or some other kind of phenomenon!