Checked for existing issues
Tested latest version
GregTech CEu Version
gtceu-1.20.1-8.0.0-SNAPSHOT+20260601-111212-2ec385c
Minecraft Version
1.20.1 Forge
Recipe Viewer Installed
EMI
Environment
Singleplayer
Cross-Mod Interaction
Unsure
Other Installed Mods
- Minecraft (1.20.1)
- Forge (47.4.0)
- GregTech CEu (8.0.0-SNAPSHOT)
- Applied Energistics 2 (15.4.10)
- Advanced AE (1.3.5)
- AE2AddonLib (1.0.4)
- EMI (1.1.22)
- JEI (15.20.0.129)
- Jade (11.13.2)
- GeckoLib (4.8.3)
- LowDragLib (1.0.40.b)
- Architectury (9.2.14)
- Configuration (3.1.0)
- Bad Packets (0.4.3)
- GuideME (20.1.14)
- Spark (1.10.53)
Expected Behavior
When I click on a pattern in the ME Pattern Buffer slot to remove it, the pattern should be pulled out of the slot and returned to my inventory. No crash should occur.
Actual Behavior
The game crashes immediately with a NullPointerException when I attempt to pull a pattern out of any slot in the ME Pattern Buffer.
Steps to Reproduce
Place ME Pattern Buffer
Open the buffer GUI
Insert any processing pattern into any slot (e.g., 1 cobblestone → 1 stone)
Click on the pattern slot to pull the pattern back out
Game crashes instantly
Additional Information
Works perfectly in GT 7.5.3 — no crash with the exact same steps
Crash occurs in new worlds, no save corruption
Crash log shows NPE in NetworkCraftingProviders$ProviderState.mount because pattern is null
The crash happens at MEPatternBufferPartMachine.update() line 216 when ICraftingProvider.requestUpdate() is called
The issue appears to be that detailsSlotMap contains a null key for the pattern being removed
Full crash log attached: [crash-2026-06-01_22.59.10-server.txt]
crash-2026-06-01_22.59.10-server.txt
Checked for existing issues
Tested latest version
GregTech CEu Version
gtceu-1.20.1-8.0.0-SNAPSHOT+20260601-111212-2ec385c
Minecraft Version
1.20.1 Forge
Recipe Viewer Installed
EMI
Environment
Singleplayer
Cross-Mod Interaction
Unsure
Other Installed Mods
Expected Behavior
When I click on a pattern in the ME Pattern Buffer slot to remove it, the pattern should be pulled out of the slot and returned to my inventory. No crash should occur.
Actual Behavior
The game crashes immediately with a NullPointerException when I attempt to pull a pattern out of any slot in the ME Pattern Buffer.
Steps to Reproduce
Place ME Pattern Buffer
Open the buffer GUI
Insert any processing pattern into any slot (e.g., 1 cobblestone → 1 stone)
Click on the pattern slot to pull the pattern back out
Game crashes instantly
Additional Information
Works perfectly in GT 7.5.3 — no crash with the exact same steps
Crash occurs in new worlds, no save corruption
Crash log shows NPE in NetworkCraftingProviders$ProviderState.mount because pattern is null
The crash happens at MEPatternBufferPartMachine.update() line 216 when ICraftingProvider.requestUpdate() is called
The issue appears to be that detailsSlotMap contains a null key for the pattern being removed
Full crash log attached: [crash-2026-06-01_22.59.10-server.txt]
crash-2026-06-01_22.59.10-server.txt