The TNT renders a block away from where it was placed once lit. Note that it still blows up where it was originally placed and the shadow is where it was originally placed as well.
Environment
Java 1.8.0_51 64 bit
Intel Core i7
MSI GP73 Leopard 8RE laptop
Thank you for your report!
We're actually already tracking this issue in MC-165133, 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.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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