java.lang.NullPointerException: Updating screen events

What the log looks like

java\.lang\.NullPointerException: Updating screen events
Description: Updating screen events

How to fix it

1. Open the crash report and read the very first 'at ...' line directly under 'java.lang.NullPointerException: Updating screen events' to identify which mod owns the crashing code (for example, 'appeng' for Applied Energistics 2 or 'notenoughupdates' for NEU), and check the '-- Affected screen --' section below it.
2. Update the mod named at the top of the stacktrace—along with any GUI or recipe overlay mods involved in the trace such as NEI, JEI, or NotEnoughUpdates—to the latest stable release for your Minecraft version, or downgrade if you recently installed a beta build.
3. If the crash triggers when clicking or looking up a specific item or recipe, test with default settings by moving that mod's configuration file out of the 'config' folder so it regenerates cleanly.
4. If the stacktrace lists only 'net.minecraftforge' or 'net.minecraft' GUI classes (such as 'GuiListWorldSelectionEntry'), remove any custom modifications made directly to 'minecraft.jar' (jarmods) and reinstall a clean Forge instance in your launcher.

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