Hologram
"As you have already guessed by looking at the footage above, it's not a hologram, it's the classic Pepper's Ghost illusion in which a moving image is mirrored onto a sheet of glass on stage."
Ah yeah, but don't forget french hacks generally have lower tech skills than my cats (yes, they have, they learnt how to bypass the cat door security, when there is no battery anymore and should not been allowed in).
Any serious computer is deemed "a full load of technology", which, in itself, says it all: I can't understand all buzz words ...