When placing an armor piece with a trim into any inventory slot, the slot gets a visual overlay showing the trim.
The issue is that after removing the trimmed armor and placing a different, untrimmed armor piece into the same slot, the trim overlay incorrectly remains, making it appear as if the new armor also has a trim.
The glitch only disappears after closing and reopening the world.
This issue is being tracked at MCPE-187679.