This change prevents issues arising from partial generation of MapChunks, which are liable to be regenerated completely when ungenerated MapBlocks within are encountered.
Co-authored-by: Po Lu <luangruo@yahoo.com>
Co-authored-by: sfan5 <sfan5@live.de>
behavior change: newly generated blocks are no longer momentarily activated.
this shouldn't matter for anyone and did not consistently apply to all blocks anyway
addresses issue from #15902 for new maps(!)