Hey, I know this bug often was reported, and often marked as duplicated. I tried to use the workaround, but 1., my custom trades are away, and 2., it does'nt work better...
- And I tried it with summon a villager in 1.14.2 and 1.14.3, and then open it in 1.14.3. It closes. 😞
The custom villager trade menu close it by its self. When you put a "buy-item" in your hand. Then the villager shows the "sell-items" in his hand.
What I expected to happen was...:
The menu keep open until I closed.
What actually happened was...:
The menu open for very short time and closed than.
Steps to Reproduce:
1. Summen a villager with a costum trade.
2. Try to trade with the villager.
( I copied this text because my english is very bad 😞 )
Maybe you can fix it.
~TomatoCake
Related issues
duplicates
Comments

To repeat: The issue MC-154201 still exists in 1.14.3; it is fixed in 1.14.4-pre1 which is a development snapshot for 1.14.4 (which has not yet released).
Please do not deliberatively create duplicate reports. This issue is fixed starting 1.14.4 pre-release 1.