If you are trading with a villager, (paper for example), there is a 20% chance each trade will unlock the villager. But in MCPE, this will never unlock the trade you are currently doing, so if you lock the paper trade, but the villager gets the particle effects that indicate he has unlocked, paper will still be locked.
Furthermore, when a villager unlocks, you generally have to open, close, and reopen the trade window in order to see trades unlocked. (Paper will still be locked, however).
This bug is serious because it is very difficult to keep a villager from becoming useless for trades if he doesn't have a large number of available trading options.
Linked issues
is duplicated by 2
Comments 3
Confirmed affects 1.0.4 and 1.0.5 on Win 10 64 bit. I haven't experienced having to open then close, then reopen, but do experience last locked trade not unlocking. If multiple trades locked, only last trade remains locked after villager clears trades. This behavior occurs consistently every time villager unlocks.
Affects 1.0.6.0