I built a Mob Grinder and within it there are no lighting sources, It's like the light is passing right through the Solid blocks (Not half slabs) and lighting up the entire inside of the mob farm. It is at the top of the map. It should be completely dark inside it but it's like the blocks are emitting their own light source (No, they're not lanterns or glow stone blocks).
I've uploaded my world to Mediafire and the save point is on the mob farm itself. If you break into it (distinguished slab wall area) you'll see what I mean. Especially during the daytime.
This bug is rendering the mob grinder pretty useless during the day. Works fairly well at night but not as well as it should. Using Full Solid Blocks, not Half Slabs
Link to the file is at http://www.mediafire.com/download/j724q7p6e3y917v/Invisible_Light_Source.rar
Updated Save using Patch 10 - https://www.mediafire.com/?dsms6lpzjeydabt
UPDATE - Dec 28th- Now that I have a PS4 it seems to happen on that console also.
I created a video for you to see if it helps you with the lighting glitch where light appears from an invisible light source.
Level: X: -8, Y: 15, z: 83
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