Fix 26.2 login success/sessionId and play login onlineMode fields - #1216
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Fix 26.2 login success/sessionId and play login onlineMode fields#1216robertvandervoort wants to merge 1 commit into
robertvandervoort wants to merge 1 commit into
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ClientboundLoginFinishedPacket (login success) now includes a server sessionId UUID after the GameProfile. Without it, protodef reports a 16-byte partial read on every join. ClientboundLoginPacket (play login) now includes onlineMode before enforcesSecureChat. Without it, the onlineMode byte is consumed as enforcesSecureChat and one byte is left unread, so clients mis-read whether secure chat is enforced. Verified against decompiled: - ClientboundLoginFinishedPacket(GameProfile, UUID sessionId) - ClientboundLoginPacket(..., boolean onlineMode, boolean enforcesSecureChat) Tested live against Spigot 26.2 (protocol 776): partial-packet warnings drop to zero; login.onlineMode=true and enforcesSecureChat follows server enforce-secure-profile.
This was referenced Aug 9, 2026
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Summary
Fixes incomplete 26.2 protocol definitions that cause partial packet reads on every join.
Verified against decompiled Spigot/NMS 26.2:
login.toClient.success/ClientboundLoginFinishedPacketsessionId: UUIDafter the GameProfile fields.Chunk size is N but only N-16 was read).play.toClient.login/ClientboundLoginPacketonlineMode: boolimmediately beforeenforcesSecureChat.(…, worldState, onlineMode, enforcesSecureChat).onlineModeis consumed asenforcesSecureChatand 1 byte is left unread, so clients mis-read whether secure chat is enforced.Test plan
partial packet/Chunk size is … but only … was readwarnings forsuccessandlogingo to zerologin.onlineMode === trueandlogin.enforcesSecureChatmatches serverenforce-secure-profileNotes
Base is
pc_26_2as requested by the automated 26.2 data PR workflow.