Bees sting through Glass Panes

What I expected to happen was...:
When aggravating a bee, standing behind glass panes prevents said bee from being able to attack me.
 
What actually happened was...:
The bee managed to attack me.
 
Steps to Reproduce:
1. Aggravate a bee through any means.
2. Stand behind and up against a glass pane perpendicular to the direction of attack (preferably where their pathfinding uses the pane as their only route).
3. Wait to be damaged.
4. Profit