Scroll bar of the villager trading UI becomes purple when there is an enchanted weapon in the inventory, including the hotbar

The bug

The scroll bar of the villager trading UI becomes dark purple if there is an enchanted weapon in the inventory or the hotbar. If you hold an item with your mouse, the scroll bar would become normal, if you have multiple enchanted items, the scroll bar will still become color dark purple. Holding a shield or any enchanted item in the offhand will prevent the issue from happening.

Resolved issues that maybe related to this issue: MC-115046, MC-102888, MC-153216, MC-129527.

How to reproduce

2019-07-27 14-29-39.mp4