Despite being surrounded by obsidian, TNT can explode blocks outside of an obsidian structure.
To reproduce this bug, place a TNT block in the air and near the ground. I used dirt blocks in the example. Then, cover all but the top with obsidian. Fly on top of the structure, and prime the TNT. Before the TNT detonates, cover the top with a block of obsidian. After the TNT explodes, several dirt blocks are destroyed.
The expected result should not have any destroyed blocks because the obsidian should block the explosion.
Thank you for your report!
We're actually already tracking this issue in MC-27077, so this ticket is being resolved and linked as a duplicate.
However, that ticket has been resolved as working as intended, which means that this is not considered a bug and won't be fixed.
Please be sure to use the search feature before creating a ticket to see if the issue has already been reported.
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