When a dispenser is powered, and contains such items like buckets and flint&steel, it continually uses it while the signal is on. Does not happen with arrows, potions or blocks. I haven't done complete testing, but it seem like it only affect buckets and flint&steel.
At first I noticed this bug while in creative, wanting to use dispensers to light things up. While receiving one signal, it continually uses the item. The same with buckets, there's no way to predict whether the water will be picked up or not as it rapidly pulses.
Related issues
is duplicated by
MC-10978
dispenser fires every tick when being powered by redstone repeaters
MC-10989
Dispenser Bug
MC-10990
Droppers dropping upon loosing power/Droppers ignoring comparators
MC-11017
Dispensers fire when updated by non-redstone updates
MC-11083
Powered dispensers & droppers recieving block updates will activate.
MC-11101
broken dispenser
MC-11112
Dispensers
Comments
migrated
migrated
Confirmed. It appears as if the act of dispensing lava (or water) is behaving like a redstone update and causing the dispenser to activate again.
migrated
It looks like constantly powered dispensers and droppers are now firing on block updates. The water placement is an update so causes this loop.
The previously existing redstone update dispenser bug is here: https://mojang.atlassian.net/browse/MC-846
migrated
confirmed on windows vista
migrated
If a powered dispenser is updated (by putting a block next to it) it will fire. Putting a water bucket in will update it then keep firing because of the water going in and out and continuously updating it.
migrated
Confirmed so anoying windows 7
Jens Bergensten
Confirmed.