I start Minecraft from the launcher, start finalizing and then suddenly disappear. From the task manager it looks like launcher and minecraft.exe still running.
16:23:56.142
launcher
main
Using default game log configuration client-1.21.2.xml (outputs XML)16:23:58.612
com.mojang.datafixers.DataFixerBuilder
Datafixer Bootstrap
263 Datafixer optimizations took 980 milliseconds16:24:01.218
com.mojang.authlib.yggdrasil.YggdrasilAuthenticationService
Render thread
Environment: Environment[sessionHost=https://sessionserver.mojang.com, servicesHost=https://api.minecraftservices.com, name=PROD]16:24:01.228
fqq
Render thread
Setting user: FoKiraly16:24:01.343
fqq
Render thread
Backend library: LWJGL version 3.3.3+516:24:01.344
fqq
Render thread
Detected unexpected shutdown during last game startup: resetting fullscreen modeAttachments
Comments 2
Thank you for your report!
However, this issue is Incomplete
Your report does not contain enough information. As such, we're unable to understand or reproduce the problem.
You are welcome to create a new ticket about your issue with more detailed information. In case of a game crash, be sure to attach the crash report from minecraft/crash-reports/crash-<DATE>-client.txt.
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I have experienced issues like this when trying to load a modded instance while my antivirus is scanning the files the modloader is trying to load. Try restarting your PC or waiting for your AV to scan the minecraft/mod files.