When water (or lava) comes into contact with a light block (minecraft:light) it is expected to be able to flow through the light block, due to the light block having no collision, block outline, or visibility, but what it actually does instead, is that the water/lava treats the light block as if it was a normal block, and flows around it. You can reproduce this issue by making a 3x3 shape out of light blocks on the ground, and breaking the center light block, after this put water or lava in the center of the light blocks and the water will not flow in any direction. This bug is also able to cause the water/lava to float in the air, or flow in a specific path by doing a similar version of the directions I already wrote, or you can try following the images that I included below
Environment
Running on the newest version (1.21.6) with no mods, data packs or anything else that changes the game in any way from its original version.
Crazy_Seb
Thank you for your report!
We're tracking this issue in MC-221590 , so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
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