Ominous banners not stacking

Ominous banners are not stacking I have 2 different stacks of banners a stack of 14 I got from a few snapshots ago and 2 I just got a few minutes ago in the latest pre-release 4 and they will not stack together for some reason I know there was a bug like this in 1.14 that was resolved but apparently it's back vengeance

Repro steps

1. Create a world on 14.4.
2. Accumulate 14 ominous banners.
3. Exit game.
4. Boot up the game in 1.15 Pre-release 4.
5. Accumulate 2 more ominous banners.
6. Notice that the new 2 banners create a separate stack.