I had a TNT cannon set up using slime blocks in the latest snapshot. I fired it, and suddenly one of the pistons started spazzing out. When I looked, the repeater was pulsing over and over again with no redstone input.

The bug appears to take place when a repeater set to 3 ticks is given a 1-tick pulse, however in further testing I was unable to replicate the bug no matter what I did. However, the bug was not just a one-time fluke as it happened every time I fired the cannon, and breaking/replacing the repeater would not fix the bug, only reset it. The bug would happen again the next time I fired the cannon.

The repeater was at the coordinates -199, 57, 382. A link to a video tutorial of the cannon in question follows: https://www.youtube.com/watch?v=oHgtMoqcBbo.

Honestly? I don't even.