Redstone blocks now power adjacent blocks (complaining about that change is MC-92562). If this behavior is kept, all adjacent blocks need to have their power state updated when a redstone block is placed, removed, or moved by a piston.
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Comments 3
I was wondering why the redstone lamps that are not next to the redstone block but was next to the block next to the redstone block was still powered.
Fixed for a future version per Searge:
I discussed MC-5951 with @jeb_ and we decided to change the behavior of the redstone block back to what it was and fix the bug differently.
Here's a gif of this behavior in action:
http://gfycat.com/PoliticalJoyfulDore
MC-92562 is probably (hopefully) just an unintended side-effect of fixing MC-5951.