This is the most critical section of the report.

The well-known piston/chest dupe has been removed. Existing servers can still enable it via a config flag if desired.

Single-player worlds now save more reliably. No more “failed to save level.dat” errors when closing the tab.

Porting modern Minecraft (1.21+) to a browser is a significant challenge because the game's code has grown substantially since the 1.8.8 era.

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