Stained glass transparency bug while viewed as an held item.

Stained glass in hand viewed in the second F5 mode makes certain parts of the texture clear.

What I expect: it to have the normal transparency as if viewed in first person.
What really happens: transparency is messed up.

How to recreate:
1.Get any stained glass
2. Select the stained glass so it is in your hand
3. Press F5 twice
4. Look at stained glass difference from first person and that.