Cobwebs no longer block light

Cobwebs no longer block light, therefore can not be used to stop undead mobs from burning.

How to reproduce:

Create a small enclosure (1x1 base size is fine)

Place cobwebs above the enclosure

Spawn a zombie in the enclosure

You can also see that it no longer blocks light by creating a large slab of cobwebs in the sky and how there is no shadow. ( /fill ~-20 ~ ~-20 ~20 ~ ~20 web )

Observed Result:

The undead mob under the cobweb now burns during the day, and the cobwebs in the sky create no shadow

Expected Result:

The undead mob under the cobweb does not burn during the day, and the cobwebs in the sky create a shadow as though it is an opaque block, like what used to happen in an earlier version.