Old worlds without new world generations when updated to 21w41a cannot have it chunks updated when opened in 1.18.
Steps to reproduce:
1. Create a world in release 1.17.1 or any version below snapshot 21w37a
2. Update it to snapshot 21w41a
3. Update it again to release 1.18
Environment
Windows 11
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We're tracking this issue as MC-239878, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as Won't Fix, which means this is considered a bug but won't be fixed. The description of that ticket or the comments might explain the rationale. Please do not leave a comment on the linked ticket.
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