Launcher problems

HMCL Crash: Not on FX application thread During Game Launch

What it looks like in the log

java.lang.IllegalStateException: Not on FX application thread; currentThread = 启动游戏

How to fix it

  1. Update Hello Minecraft! Launcher (HMCL) to the latest stable release, as this threading bug was fixed in versions after 3.2.120.
  2. Open your profile's Version Settings -> Advanced Settings in HMCL and uncheck 'Do not check game completeness' (不检查游戏完整性).
  3. Launch the game again while connected to the internet so HMCL can automatically verify and download any missing library files.
LoadersVanilla, Forge, Neoforge, Fabric, Quilt
SeverityBreaks something
CategoryLauncher problems

Check your own log

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