I was testing scoreboard for "SeeFriendlyInvisibles" and i held i colored glass pane and it was solid

What i expected to happen:
I was expecting everything to be normal

What actually happened was...:
Glass pane was opaque and looked solid, so were stained glass blocks, wierd but it looked pretty cool...

Steps to Reproduce:
1. What i did was: "/Scoreboard Teams add Team"
2. "/scoreboard teams option team seeFriendlyInvisibles"
3. Joined the team, went invisible and held a glass pane, glass pane was opaque