Steps to Reproduce:
Create a new world (Can be reproduced more easily in a flat world);
Go to the Nether;
Die in there, while in survival mode;
Attempt to mine any block in the overworld after you respawn.
Observed Results:
The blocks you punch turn into nether related blocks.
Expected Results:
The blocks stay the same.
Screenshots/Videos attached: Yes
Notes: You must die in survival mode in order to easily reproduce this, otherwise you'll experience MC-175988.
Thank you for your report!
We're actually already tracking this issue in MC-175177, 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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