When standing on Mud or Soul Sand, the Sky and Block light levels become 0. This affects my friends as well, and is not just a mod-related issue. Pardon the mess od an F3 screen, the light levels are shown on the left side as the 4th and 5th green-named items.
[media]
Thank you for your report!
We're tracking this issue in MC-249227, so this ticket is being resolved and linked as a duplicate.
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