I have encountered either a bug or an issue where when specifying the Y level coordinates for example
873 30 343 in the nether
and when generating structures using the /place command the structures generated ignore the specified Y level parameter, this is easily replicable. (Also, some structures fail to generate when using this command) such structures such as mineshafts appear to select a pre-determined Y level regardless of which Y level has been specified . in my case it was 30 and it decided to generate on the nether roof.
Thank you for your report!
We're tracking this issue as MC-251332, 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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