Crash: Java Stop Responding when backing up world from 1.15 to 1.15.1

We do not have enough information to find the cause of this issue.

Please attach the crash report found in [minecraft/crash-reports/crash-<DATE>-client.txt|https://minecrafthopper.net/help/guides/finding-minecraft-data-folder] here.
If you cannot find a crash report, please attach the full launcher log found in [minecraft/launcher_log.txt|https://minecrafthopper.net/help/guides/finding-minecraft-data-folder/].

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I put my launcher log in

Thank you for your report!
We're already tracking this issue at MCL-6550, so I will resolve and link 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 to see if the issue has already been mentioned.

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Issue is prevalent when converting worlds from 1.15.1 to 1.15.2, and is not related to the linked “duplicate” error. Please reopen and continue.

If you go onto your launcher_log.txt that you attached and do a search for 'exit code', you'll see the same exit code as the duplicate error.