Mojira Archive
MC-280090

Trying to edit a world that fails to load due to oversized NBT tag leads to Minecraft getting stuck on "Reading world data..." screen

Bug
Trying to open a world (Play Selected World) with an oversized NBT tag will lead to an error message appearing on screen notifying you that the world failed to load. It shows you three options to click; (Report a Bug), (Attempt to Restore) if it's available, and (Back) to return to the previous menu. Trying to (Re-Create) the world will show an error message, along with a (Back) button.

Trying to (Edit) the world results in the program getting stuck trying to read the contents. A popup appears stating it failed to read the world, then gets stuck on the "Reading world data..." screen. There is no button to exit to previous menu, effectively softlocking the game. I haven't found a way to exit this state without relaunching Minecraft.

Steps to reproduce

  1. Create a world with an oversized NBT tag. This can be as simple as opening a world in vanilla Minecraft in creative mode, placing a chest and filling it with items, then pick-blocking it and filling another chest with stacks of the previous chest, and rinse and repeat until the world will no longer load due to oversized NBT. Save and quit to menu. Demonstrated below
  2. Select the affected world. Click (Edit)

Observed Behaviour

  • Info popup appears with text "Failed to access world" and world name
  • Game is stuck on "Reading world data..." screen

Expected Behaviour

  • Something similar to what happens when (Play Selected World) or (Re-Create) is clicked

Aside

If it is this easy to brick a world with oversized NBT tags maybe there should be a safety guard preventing such things from happening? or increase size limit to 200MB or smt idk

Link to video demonstration: https://drive.google.com/file/d/1TTZdEOetAFhY486S80XATzuiz8hY2e-i/view?usp=sharing

Unresolved

jimmycunk

2025-02-05, 04:49 AM

2025-02-05, 04:49 AM

0

0

Unconfirmed

(Unassigned)

1.21.4

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