Fix NPE in dimension_type registry handler for MC 26.1.1#1242
Merged
kennytv merged 1 commit intoViaVersion:masterfrom Apr 7, 2026
Merged
Fix NPE in dimension_type registry handler for MC 26.1.1#1242kennytv merged 1 commit intoViaVersion:masterfrom
kennytv merged 1 commit intoViaVersion:masterfrom
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When a player using an older client (via ViaBackwards) connects to a
26.1.1 server, the REGISTRY_DATA packet is remapped by
Protocol26_1To1_21_11. The dimension_type handler assumes every
dimension entry contains an "attributes" CompoundTag and calls
removeNamespaced() on it to strip new visual fields
(block_light_tint, night_vision_color, ambient_light_color).
In 26.1.1 some dimension_type entries may not include the "attributes"
tag at all, causing getCompoundTag("attributes") to return null.
This results in a NullPointerException inside TagUtil.removeNamespaced,
which crashes the encoder pipeline and disconnects the player with
"Internal Exception: EncoderException".
Added a null check before calling removeNamespaced so that dimensions
without the attributes tag are silently skipped.
kennytv
approved these changes
Apr 7, 2026
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When a player using an older client (via ViaBackwards) connects to a 26.1.1 server, the REGISTRY_DATA packet is remapped by Protocol26_1To1_21_11. The dimension_type handler assumes every dimension entry contains an "attributes" CompoundTag and calls removeNamespaced() on it to strip new visual fields (block_light_tint, night_vision_color, ambient_light_color).
In 26.1.1 some dimension_type entries may not include the "attributes" tag at all, causing getCompoundTag("attributes") to return null. This results in a NullPointerException inside TagUtil.removeNamespaced, which crashes the encoder pipeline and disconnects the player with "Internal Exception: EncoderException".
Added a null check before calling removeNamespaced so that dimensions without the attributes tag are silently skipped.
Example of fixed error from my server with datapack for new dimension: https://pastebin.com/M9eCv3th