From now on, villagers must be renamed using a name tag with either ‘Optimize’ or ‘Bonk’ in order to trade with them, or you must use one of the following blocks to trade: Block of Redstone, Sea Lantern, or Cobblestone. Place the blocks below the villagers, as shown in the screenshot. We took this step to reduce lag caused by villagers and large trading halls.
Do not rename villagers to trigger optimization until after they have taken a profession. Disabling AI before a job is taken will prevent them from ever accepting one.
Nametags:
Blocks:
