Minecraft v1.14.4
Forge v28.1.87
Quark r2.0-199

• Currently, most translucent blocks render incorrectly when placed underwater, and should instead render similarly to glass or slime blocks. This includes colored slime blocks, framed glass, cave crystals, etc. Lanterns could also be made to be waterlogged.

• I've also noticed that soul sandstone vertical slabs and walls use an incorrect top texture.

I have no idea why this would happen. They don't do anything different from the vanilla ones. 🤔

I figured it out, this is a forge issue. Vanilla has a hardcode to not render the water sprite on glass and stained glass.

Bluepower glass had a similar issue that I reported at Qmunity/BluePower#498, if that helps any.

I think it's only a workaround for now though