Caught on fire from lava on other side of Glass

I stand next to glass with lava on the other side and get lit on fire.

What I expected to happen was...:
Everything would be all nice and handy dandy

What actually happened was...:
It was not light, but fire that met me.

Steps to Reproduce:
1. Put lava behind glass like in the pic below
2. Stand
3. Be lit on fire

Yes, there is no lava anywhere but behind the glass