I noticed in my realm recently that there are chunks where sea lanterns are not updating. For some reason the top side of the sea lantern do not emit any light level what so ever. This is causing mobs to spawn in places that otherwise would be impossible for them to spawn. I did notice that updating blocks in that chunk can get them to turn back on. But logging out and logging back into the realm the sea lanterns go back to their unresponsive state. Also its good to note that this is not happening in all the chunks. In my case there are unresponsive chunks bordering chunks with responsive sea lanterns (see attached photo). Hopefully there is something that can be done to fix this as there are places in my world I don't need mobs spawning and due to this bug they can spawn even with the area being fully lit. Thank you for your attention to this matter. - Jorge R.
I can take more pictures of other places that are affected if need be.
Thank you for your report!
We're actually already tracking this issue at MCPE-58182, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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