Redstone climbing up the side of a block will not power the redstone component above it

Redstone wire that climbs up the side of a block will not power redstone components above it.

Steps to Reproduce:

1. Replicate the following setup:
   (One non-stackable item is in the dispenser)
   

Observed Behavior:

The piston will not be powered, despite powered redstone wire running into it.

Expected Result:

The piston (or any other block in its place) would be powered.

Screenshots/Videos: