[MC-94739] Dispenser not shooting (with pics)

This is a very strange bug and I have no idea why it happens.
Sometimes Dispensers and Droppers only fire when they receive a Block Update.
The Setup shown in the picture worked every time I built it.

Linked issues

duplicates 1

MC-108 Droppers, Dispensers and Pistons activate when blocks are providing power diagonally or two blocks above Resolved

Attachments

Comments 2

[Mod] redstonehelper 2015-12-24T04:45:40Z

The dispenser on the bottom updated before all its power inputs turned off. It didn't update after that because of MC-108.

Qendolin 2015-12-27T19:11:05Z

when you press the button it fires one time, but when you press it again it doesn't, so this is another bug. Also the dispenser is directly powered.