This isn't anything new[1][2], though it's a shame it's allowed. Apparently congressmen had to vote on it two hours[3] after receiving the 5000 page bill.
[1]https://en.wikipedia.org/wiki/Omnibus_bill
[1]https://en.wikipedia.org/wiki/Omnibus_bill
Side note, who mandates these time constraints? Why are seemingly arbitrary deadlines applied? If a bill can stand on its own, why rush it at all unless you intend to enable surreptitious changes that will hopefully be missed?