Minecraft: 1.15.2
Forge: 31.2.0
projectvibrantjourneys-1.15.2-2.0.2

Right-clicking with flint/nugget in the main hand, on the upper face of the block that's directly below a chest, will break the chest, its content will drop, but the chest itself won't because it was yeeted to the Void.
Video showing this

Nuggets and flint can replace anything, they can even replace mutually if you try hard enough. I don't think vanilla flint/nuggets should have the same behaviour as groundcover flint/nuggets

It also happens with every block that doesn't take up the full cube

Uh oops, I added a fix for it but forgot to release it. I'll push the fix out tomorrow.

Uploaded to CurseForge, should be approved soon.