Banner patterns on banners fills up the whole banner

Banner patterns don't render correctly in banners, they fill up the whole banner, making them blank. It can even be seen via, shields with a custom banner and through the advancement icon of 'Voluntary Exile'.

How to Reproduce

Ominous Banner

1. Find an outpost and find the leader with a pitch black banner that has the name Ominous Banner.

Custom banner

1. Get a loom block
2. Get dye and a banner
3. Use the loom.