I have create my fire worker spectacle in 1.11 -> it's ok.
But when I test my spectacle in 1.12 snapshot (17w13-14), the colors of fire works have missing, every fireworks are black ! Since I wait this bug correction but his not correct.
I can also see than the Life Time is not respected (in the third screenshot, the fire works must explode at ground level)

I could see that not edit in 1.12,
can you correct this bug please ?

My command :
/summon fireworks_rocket ~ ~ ~ {LifeTime:1,FireworksItem:{id:fireworks,Count:1,tag:{Fireworks:{Explosions:[

]}}}}