Suffocation overlay inside slime blocks is completely opaque

The bug

Despite the fact that slime blocks and ice both have translucent textures, and render translucent in the world, the suffocation overlay they impart on the UI when a player is inside them is rendered entirely opaque.

How to reproduce

1. Set up ice or slime blocks in a way that the player can be made to intersect them, such as them being pushed into a player by pistons
2. Have them be pushed into the player
3. Note that the screen is completely occluded and nothing of the world can be seen, despite the texture file itself and the block it applies to being translucent

Expected results

Either the suffocation overlay would be rendered translucent, or there would be no suffocation overlay at all (even if the player still suffocates).

Actual results

The translucent textures for these blocks are rendered, and are rendered completely opaque.