When you place any full block (in my case polished granite) betwen mycelium and dirt it spreads
How to reproduce
1. dig an 3x1x1 hole (like in the screenshot)
2. place dirt on 1 side then place 1 mycelium on the other side
3. block the speard of mycelium with an full block (here ive seen it spread trough polished granite)
4.wait a clople of minutes
Observed results
Mycelium spreds to the oher side
Expected results
Mycelium shouldn't spread to the other side