I did create my world with it yes. It might be working for you because yours is a local server. I'm using bisecthosting, so I don't know if its just them or all online servers.
No, the issue isn't that you can't upgrade, the issue is that the trims don't generate in loot chests.
Did you give yourself Night Vision with the {ShowParticles:False} NBT tag? If you did, just try doing /effect clear @s
Dylan Stal
I did create my world with it yes. It might be working for you because yours is a local server. I'm using bisecthosting, so I don't know if its just them or all online servers.